The Heat Your Tyre Gauge Never Sees
A caravan wheel bearing can spend weeks quietly wearing itself out without giving you a single reason to worry. No noise. No wobble. Nothing on the dash. Then, somewhere on a stretch of highway a long way from the nearest town, it stops being quiet.
That's the uncomfortable truth behind caravan wheel bearing failure: by the time you'd notice something's wrong, the bearing has usually been degrading for a while already, and the window to deal with it safely has mostly closed. Temperature is the tell. A failing bearing generates heat well before it makes noise or you can feel a wobble through the tow, and that heat builds at the hub first, not the tyre. A standard tyre pressure sensor reads the air inside the tyre. It was never built to watch the hub, and any heat from a failing bearing has to travel through the hub, the wheel, and the rim before it shows up there at all, if it ever really does in a form the sensor would flag as unusual.
Picture a fairly ordinary scenario: an hour into a five-hour leg, somewhere between towns, everything feels normal. The van's tracking straight, the tow vehicle isn't working any harder than usual, and there's nothing on any gauge to suggest a problem. Underneath, on one wheel, a bearing that took on a bit of water during last week's creek crossing has already started running hotter than it should. Nothing about the drive gives that away. That's the entire problem in one scenario: the failure is real and already in progress, and there's currently no reason for anyone in the vehicle to suspect it.
That gap between where the heat starts and where a sensor is actually looking matters more than it sounds like it should. A standard tyre pressure monitoring system, or TPMS, is built to watch the valve stem, reading tyre air pressure and temperature. That's genuinely useful information. It just isn't information about your wheel bearings, because the bearing sits at the hub, a good distance away through metal and rubber that heat has to fight its way across before a valve-stem sensor notices anything unusual, if it notices at all.
This isn't the most common way a caravan catches fire on the road, and it wouldn't be honest to pretend otherwise. Cooking appliances and electrical faults cause more caravan fires than wheel bearings do. What makes wheel bearing failure worth understanding on its own terms is that it's one of the few caravan fire and breakdown risks that's genuinely preventable if you're watching the right number, and almost impossible to catch if you're not.
That's the shape of this article: why wheel bearings fail in the first place, what happens when nobody's watching, why the TPMS a lot of caravan owners already run doesn't cover this particular failure mode, and what actually does. Along the way, there's an honest look at how big a risk this really is next to the more common ways caravans catch fire, because a safety argument only holds up if it survives that comparison.
How a Wheel Bearing Actually Fails
A wheel bearing has one job: let the wheel spin freely around the axle while carrying the full weight of the caravan and whatever's loaded into it. It's a small, sealed assembly of steel races and rolling elements packed in grease, and under normal conditions it can run for tens of thousands of kilometres without complaint.
Caravan bearings don't get normal conditions. A car's wheel bearings deal with the car's own weight and the occasional pothole. A caravan's bearings deal with a fully loaded trailer, hour after hour, often at highway speed, sometimes on corrugated dirt, sometimes through water crossings, and frequently sitting idle in a caravan park for weeks between trips while seals dry out. That combination of sustained load and inconsistent use is harder on a bearing than most owners realise.
Bearings fail for a handful of reasons, and lubrication problems cause most of them. Too little grease, the wrong grease, or grease that's been contaminated or broken down by heat and time accounts for roughly 80% of bearing failures, according to automotive bearing-failure analysis from sources including Ricks Free Auto Repair Advice and Bartlett Bearing's 2026 technical guide. Water ingress through a failed seal is the next biggest factor: once water gets into the bearing cavity, it washes out the grease's protective properties and starts corrosion almost immediately, per Machinery Lubrication's engineering research. Mechanical damage from potholes, overloading, or a bearing that wasn't seated correctly during a service accounts for most of what's left, alongside straightforward fatigue after enough kilometres of use.
It's worth being upfront about that 80% figure. It comes from general automotive and industrial bearing-engineering literature, not a study specific to caravans or RVs. Nobody appears to have run a dedicated academic study on caravan wheel bearing failure rates in particular, so treat it as solid industry consensus rather than a precise measurement of caravan bearings specifically. It does line up with what caravan owners report on forums like Exploroz and the Practical Caravan Forums, where premature bearing failure and re-greasing routines are recurring topics, especially among owners doing serious kilometres.
Here's what all four failure paths have in common: heat. Whether the root cause is a dry bearing grinding metal on metal, a corroded race from water contamination, or a bearing pushed past its rated load, the mechanism that follows is the same. Friction increases. Temperature climbs. That's exactly why temperature, not noise or vibration, is the earliest reliable signal something is wrong.
Most caravans use tapered roller bearings rather than the ball bearings common in car hubs, because tapered rollers handle the combination of radial and side-loading a heavy trailer puts on a wheel far better under sustained towing. That's also why the maintenance culture around caravan bearings looks different to car servicing. Nobody schedules a dedicated "wheel bearing check" as part of a normal car service unless something's already making noise. Caravan manuals, by contrast, usually specify a re-grease interval, because the manufacturer already knows the bearing needs attention on a predictable schedule, not just when it fails.
A well-maintained bearing, properly greased and never contaminated, can comfortably outlast several sets of tyres. That's part of why they're easy to overlook: most owners replace tyres on a predictable schedule because tread wear is visible, but a bearing gives no equivalent visual cue until something has already gone wrong. Replacement parts themselves aren't expensive, a bearing kit typically costs well under $100, but the labour, the diagnosis, and the disruption to a trip cost considerably more than the part itself ever does.
The classic warning signs, a grinding or humming noise from the wheel, a faint wobble through the tow ball, a hub that's noticeably hot to the touch after a run, are all real. They're just late. By the time any of them show up, the bearing has typically been degrading for some time already, which is exactly why what happens next is worth understanding in more detail.
From Silent Heat to Wheel-Off: What Happens When Nobody Catches It
So what does that gap between "fine" and "failed" actually look like? It starts quietly and ends fast.
Industry guidance on trailer hub temperature breaks the problem into bands, and they're worth knowing. Up to around 130°F (54°C) is normal operating range for most trailer hubs at highway speed. Between 130°F and 170°F (54-77°C) counts as elevated: worth watching and comparing side to side, but not necessarily an emergency on its own, especially in hot weather or under heavy load. From 170°F to 220°F (77-104°C) is a genuine warning zone, and the standard advice is to pull over at the next safe opportunity and inspect. Above 220°F (104°C), the guidance gets blunt: stop immediately, because bearing damage is likely and hub fire risk is imminent, according to TrailerWatchdog's technical guidance, updated March 2026.
What those bands describe is a progression, not a single moment. A bearing beginning to break down typically moves through recognisable stages: early wear with a barely noticeable temperature rise, excessive play as surfaces degrade and temperature climbs further, metal-on-metal contact as grease depletes and temperature spikes, and finally seizure, where the hub can overheat to the point of glowing and the wheel is at genuine risk of separating. None of the early stages make noise or show up on a tyre pressure reading. By the time there's a smell of hot grease or visible smoke, the problem has usually already moved well into that progression, hot enough in the worst cases to ignite brake fluid or damage the axle and suspension components around it.
This isn't theoretical. The US National Highway Traffic Safety Administration has issued federal safety recalls over exactly this failure chain. One, recall 23V-230 from 2023, covered certain Great Dane Champion Dry Van trailers fitted with a preset hub system that may have shipped with an inadequate lubricant fill, warning that insufficient lubrication could lead to catastrophic hub bearing failure and cause the wheel, tyre, and hub assembly to detach from the vehicle. A separate 2023 recall, 23E057, covered RevHD hub caps over a defect that could let wheel bearings overheat, seize, and cause a wheel-end fire or a wheel-off condition. Both recalls concern commercial trailers rather than private caravans, but the physics don't change based on what's being towed. Heat builds, the bearing seizes, and depending on exactly how it fails, you're looking at either a fire risk or a wheel that's no longer attached to your caravan, sometimes both.
It's also worth noting that a caravan wheel separating on tow doesn't just risk the caravan itself. A wheel and tyre coming off at highway speed becomes a hazard for following traffic, and the caravan's remaining wheels suddenly have to carry a load they weren't set up to handle unassisted. The consequences of a bearing failure rarely stay contained to the one component that actually failed.
Real-world accounts back this up in less clinical language. On Forest River Forums, one owner described a bearing seizing and the wheel coming off entirely, with the resulting friction starting a fire. A separate account on iRV2 described a wheel bearing failure severe enough that the axle itself got hot enough to break, the wheel came off, rolled into dry grass beside the highway, and started a grass fire. These are forum posts, not data points, and they describe US trailer incidents rather than confirmed Australian caravan cases, but the mechanism they describe, heat, seizure, separation, ignition, is the same one NHTSA's recall documentation describes in more formal language.
None of this happens instantly, and that's really the whole point. There's a meaningful stretch of time, typically minutes to hours according to TrailerWatchdog's own technical guidance, between a hub starting to run warm and a hub becoming genuinely dangerous. That stretch is the entire opportunity. Whether it gets used productively, pulling over, checking the wheel, calling for help before anything worse happens, or wasted entirely depends on whether anything is actually watching hub temperature during that window. For most caravans on the road today, nothing is.
There's a second consequence that gets less attention than fire but happens more often in practice: the plain old breakdown. A seized bearing on the side of the road isn't a five-minute fix. It usually means a tow truck, a wheel and hub assembly that needs replacing, and depending on where you are, a wait that stretches into days rather than hours. Fire is the dramatic outcome. A stranded caravan a long way from the nearest workshop is the far more common one, and it's still expensive and disruptive enough to be worth avoiding on its own.
The risk isn't distributed evenly across every caravan, either. Heavier vans, dual-axle setups carrying more weight per bearing under sustained highway speed, and vans that see plenty of dirt road or water crossings all load their bearings harder than a lightly used single-axle van doing mostly bitumen. None of that makes a lighter setup immune, a lubrication failure doesn't check your registration first, but it does mean the risk scales with exactly the kind of touring a lot of Australian caravan owners do for fun.
Why Your TPMS Can't See This Coming
If you already run a tyre pressure monitoring system on your caravan, it's worth being precise about what it's actually watching, because "TPMS" can sound like it covers more ground than it does.
A standard TPMS sensor screws onto the valve stem and reads two things: air pressure inside the tyre, and the temperature of that air. Both are genuinely useful. Pressure loss is one of the more common causes of tyre failure on tow, and catching it early is exactly what a system like this is built for. Temperature at the valve stem can also flag an overheating tyre caused by underinflation or a dragging brake.
What it can't do, structurally, is measure the wheel bearing, because the bearing isn't at the valve stem. It's at the hub, on the other side of the wheel, separated from the tyre's air cavity by the wheel itself and whatever's between them. Heat generated at a failing bearing has to travel through that structure before it reaches anywhere a valve-stem sensor can detect it, and there's no guarantee it ever does so in a form the sensor would flag as abnormal. TrailerWatchdog, a company that builds dedicated hub-temperature sensors, puts it plainly: bearing seizure, a dragging brake, and a failing grease seal "don't show up on a tire pressure gauge," and the first sign is too often smoke, flames, or a wheel that's no longer attached.
Think about the physical path the heat has to take. The bearing sits inside the hub assembly, packed in grease, sealed off from the outside. When it starts running hot, that heat first has to conduct through the hub itself, then through the wheel and rim, before it can meaningfully raise the temperature of the air sealed inside the tyre, which is what a valve-stem sensor actually reads. Metal conducts heat reasonably well, but there's still mass to heat up and distance for that heat to travel, and none of it happens instantly. That's the physical reason the lag exists, not a limitation of any particular sensor's electronics, but a limitation built into where the sensor sits. It's a bit like trying to tell whether a pot on the stove is boiling by touching the outside of the kitchen door: eventually some warmth makes its way through, but a thermometer actually in the pot tells you sooner, and more precisely, every time.
That gap matters more than it sounds like it should. It's the difference between catching a bearing in the early, recoverable stages of failure, and noticing it only once smoke, a burning smell, or a wobble makes it impossible to ignore, by which point the bearing has typically already progressed to metal-on-metal contact or worse.
To be fair to the rest of the industry, not every competing system pretends this gap doesn't exist. TST, a well-regarded US trailer TPMS brand, states directly on its own site that overheating detected in the tyre cavity "can be caused by a number of reasons: underinflated, failing wheel bearings, and dragging brakes," and that's a genuine claim worth taking seriously. It's just an indirect one. TST's sensors still read temperature from inside the tyre cavity, not from the hub itself, which means the warning is real but arrives however long it takes hub heat to reach the tyre, if it reaches a detectable level there at all. It's an early warning that's better than nothing, but later than a sensor actually sitting on the hub would manage. Other systems, including Tymate's consumer TPMS lineup, don't make any bearing-related claim at all. They monitor tyre pressure and internal tyre temperature and stop there, with no visibility into what's happening at the axle. TireMinder's current product pages don't make a specific bearing-detection claim either, at least not in the materials reviewed for this article. EEZTire's and GUTA's current lineups weren't confirmed either way during research, so they're treated here as open questions rather than confirmed gaps; it's always sensible to confirm a system's exact feature set against the specific model being considered rather than a general brand description.
None of this is a criticism of TPMS as a category. Tyre pressure monitoring solves a real and common problem, and any caravan towing regularly benefits from having one fitted. It's simply a different problem to the one a failing wheel bearing presents, and conflating the two is how someone ends up assuming their existing safety tech has a blind spot covered that it doesn't. If you're still working out the basics of what a TPMS actually does and which kit fits your setup, iCheckTPMS's complete guide to tyre pressure monitoring covers that ground before you get to the bearing-specific question this article is about.
If the lag exists because the sensor is in the wrong place, the fix is obvious once you say it out loud: put a sensor in the right place. Not inferring hub temperature from the tyre, several steps removed from where the heat actually starts, but measuring it directly, at the hub, where a bearing failure actually begins.
The Silent Window Between Services
Even the best-maintained caravan bearing operates on a schedule, and that schedule has gaps built into it by design.
Standard guidance for Australian caravans and trailers is to inspect and re-grease wheel bearings every 10,000km or 12 months, whichever comes first, tightening to every 5,000km or 6 months if the van sees regular off-road use or heavy, frequent towing, according to service guidance from Superior Trailer Parts and RV Daily. That's sound advice, and following it is genuinely one of the most effective things an owner can do to avoid a bearing failure in the first place.
It's also, by definition, a schedule that assumes the bearing behaves predictably between checks. A bearing doesn't know what the manual says. A water crossing that gets a bit of moisture past a seal, a grease job that wasn't quite thorough enough, an unusually rough stretch of corrugated track: any of these can accelerate wear well inside that 10,000km window, and the bearing has no way of flagging that it's now running ahead of schedule. The service interval protects against the average case. It doesn't protect against the one trip where something went slightly wrong.
There's also a simpler, less technical reason the gap matters: not every owner sticks to the schedule as closely as the manual assumes. Caravans sit unused for months at a time, service intervals get pushed back around a big trip instead of before one, and life gets in the way of a bearing service as much as anything else. None of that makes anyone a careless owner. It does mean the real-world gap between "should have been checked" and "actually checked" is often longer than 10,000km, which makes a way to catch a developing problem inside that gap more useful, not less.
Picture the alternative to a fixed calendar reminder: a system that doesn't care what the manual says the schedule should be, because it's actually watching the bearing itself rather than assuming based on kilometres travelled. A caravan owner who greases religiously every 10,000km on the dot still has no way of knowing, on kilometre 4,000 of that cycle, whether everything's fine or whether last week's water crossing has already started a slow problem. Continuous monitoring answers that specific question, on that specific day, rather than waiting for the next scheduled check to find out.
That's the actual argument for continuous monitoring, and it's a narrower, more honest one than "you need this because bearings fail." Servicing your bearings on schedule is still the foundation. Monitoring doesn't replace that. What it does is cover the months between services, the exact stretch of time the schedule has to assume is fine because there's no other way to know. It's the same logic iCheckTPMS already applies to tyre pressure through InstaData™, checking in every five minutes whether the caravan is moving or parked, rather than waiting for a problem to become visible or audible. Applying that same continuous-check logic to the hub, instead of just the tyre, closes the specific gap a fixed service interval can't.
None of this is an argument against servicing. If anything, it's the opposite: a bearing that's watched continuously and serviced on schedule is about as well covered as a wheel bearing can reasonably be. It's the caravans doing one of those two things without the other that carry more risk than their owners probably realise.
Let's Be Honest About the Odds
Here's a fact that doesn't get said often enough in articles like this one: wheel bearing failure is not the leading cause of caravan fires. Not close, actually. According to RAC WA, cooking appliances start more caravan fires than anything else, with electrical faults, faulty wiring, and overloaded circuits in second place, and lithium-ion battery fires from portable devices climbing as a newer third cause. Wheel bearings don't crack the top of that list.
It would be easy to skip past that fact in an article making the case for bearing monitoring, and it would also be dishonest. Queensland's Fire Department attended 341 caravan and camper trailer fires in the five years to June 2025, a real and sobering number, but it's a total across every cause, cooking, electrical, gas, batteries, and everything else, not a wheel-bearing-specific count. Nobody appears to have published a breakdown of exactly what share of caravan fires trace back to a bearing, in Australia or anywhere else, and it would be making up a number to imply otherwise.
So why does wheel bearing failure deserve its own article at all, if it's not the biggest risk on the list? Because it's arguably the most preventable one, and that's a different, more useful claim than "most common." A stove left unattended or a wiring fault in an ageing caravan isn't something a temperature sensor is ever going to catch. A wheel bearing quietly overheating for ten or fifteen minutes before anyone notices is exactly the kind of problem a sensor watching the right spot can catch early, every time, with no judgement calls involved. Of everything on RAC WA's list, it's the one failure mode where "we could have known sooner" is actually true given the right monitoring, rather than wishful thinking.
That distinction matters for anyone deciding where to spend a limited safety budget on caravan upgrades. A smoke alarm and a fire extinguisher address the higher-frequency risks, cooking and electrical faults, directly, and every caravan should carry both regardless of anything in this article. It also helps to think about what a wheel bearing sensor can't do, since being clear about the limits of any single piece of safety gear is part of being honest about what it's worth. It won't stop a fire that starts in the kitchen, won't fix faulty wiring, and won't do anything for a battery that's been damaged or improperly charged. Those risks need their own solutions: interconnected smoke alarms rated for the caravan environment, a properly maintained gas system, and an electrical setup checked by a qualified auto-electrician if there's ever any doubt. A wheel bearing sensor solves exactly one problem well. It was never going to solve all of them, and no single product ever does.
Bearing monitoring addresses a lower-frequency risk that happens to be unusually well suited to sensor-based prevention, which makes it a sensible addition rather than a replacement for the basics. That's a fair trade whether you're touring the East Coast for a fortnight or attempting something considerably longer.
Why This Matters More on Australian Roads
Everything so far applies to any caravan anywhere. Some of it matters more if you're towing in Australia specifically, and the reason comes down to scale and distance.
Australia's registered RV and caravan fleet hit 937,000 vehicles in 2025, an all-time record and a 4% increase on the year before, according to the Caravan Industry Association of Australia's State of the Industry 2026 report. That works out to roughly one RV for every 29 Australians. Australians took 17.3 million caravan and camping trips in 2025 alone, generating close to $12.6 billion in trip-related spending. Caravanning in this country isn't a niche hobby. It's a genuinely mainstream way a very large number of people spend their time off.
Average trip length actually fell to 3.4 nights in 2025 as more owners took shorter, more frequent trips rather than one long expedition. But shorter individual trips don't necessarily mean less cumulative distance over a year, and plenty of weekend-and-long-weekend travellers rack up just as many kilometres across a season of short trips as one long-haul traveller does in a single extended lap. The distance adds up regardless of how it's split across the calendar.
For those who do go long, the "Big Lap", a full circumnavigation of the country via Highway 1 and whatever detours look interesting along the way, covers something like 14,500km on the highway alone, and closer to 25,000 to 30,000km once side trips into places like the Red Centre, Cape York, or Tasmania get added in. Depending on pace, that trip can take anywhere from six weeks to a full year, with six months being a commonly cited timeframe among grey nomads working their way between Broome and Esperance.
Run the maths on a trip like that against a 10,000km service interval, and the arithmetic gets uncomfortable. A single extended lap can pass through two, three, or more standard bearing service windows in one continuous trip, frequently in parts of the country where the nearest town, let alone the nearest workshop, is hours rather than minutes away. A bearing failure forty minutes outside Broome is a genuine inconvenience. The same failure four hours down a remote stretch of the Gibb River Road, or well into the Nullarbor with patchy phone signal, is a considerably more serious problem, and it's exactly the kind of situation where a bit of early warning is worth a great deal more than it would be on a Sunday drive twenty minutes from home.
Roadside assistance coverage itself changes with distance from town, too. NRMA, RACQ, and RACV all offer some form of Australia-wide cover, but response times in remote areas can run to many hours rather than the same-day service standard drivers expect closer to the major cities, and some remote tracks fall outside standard coverage entirely. None of that is a reason to avoid remote travel. It's a reason to want as much advance warning as possible before a slow mechanical problem becomes a stranded one.
The US market faces a version of the same equation at a different scale. RV shipments there finished 2025 at 342,220 units, with an estimated 8.1 million American households owning one, and towable RVs (travel trailers and fifth-wheels, rather than motorhomes) making up the large majority of that fleet, according to RV Industry Association data. The physics of a failing bearing don't change with the border. A lot of what applies to an Australian Big Lap applies just as directly to a long-haul US RV trip through country where help isn't around the next bend either.
Whichever pattern describes your own towing, weekend trips or a full lap, the same basic fact holds: the further you get from help, the more a few minutes of warning is worth.
Direct Hub Monitoring vs. Guessing From the Tyre
Everything up to this point has been about the problem. Here's what actually closes the gap.
A hub-mounted temperature sensor does something conceptually simple: it measures temperature at the hub itself, where a bearing failure actually starts, rather than several steps removed at the tyre valve stem. iCheckTPMS's Wheel Bearing/Hub Temperature Sensors are exactly this: a physically separate sensor from the standard tyre sensor, mounted directly on the wheel hub, reporting temperature straight to the same monitor already displaying tyre pressure and temperature data. Readings update via InstaData™, the same technology that already refreshes tyre data every five minutes whether the caravan is moving or sitting still in a caravan park, so a hub running hot doesn't wait for the vehicle to be underway before it shows up on the display.
The table below lays out the practical difference between a standard valve-stem TPMS reading and a direct hub-mounted sensor, based on the product information and technical claims currently published for each brand:
| Brand | Sensor location | What it can flag | Direct hub/bearing sensor |
|---|---|---|---|
| Oricom TPS10 series | Valve stem | Tyre pressure and temperature only; no bearing-related claim found | No |
| TireMinder | Valve stem | Tyre pressure and temperature only; no specific bearing-detection claim found in current product materials | No |
| TST 507 | Tyre cavity | Tyre pressure and temperature; markets unusual heat as a possible indirect sign of a dragging brake or bad wheel bearing | No |
| Tymate | Valve stem | Tyre pressure and temperature only; no bearing-related claim | No |
| iCheckTPMS (with Wheel Bearing/Hub Temperature Sensors) | Hub-mounted, physically distinct sensor | Hub/bearing temperature directly, on the same display as tyre pressure and temperature | Yes |
It's worth being precise about what that table does and doesn't claim. Of the systems reviewed, none offer a sensor physically mounted at the hub the way iCheckTPMS's add-on does, which is a meaningful and verifiable difference. That's a narrower, more defensible claim than "world's first," language that appears in some of iCheckTPMS's own marketing but which no independent source has confirmed, so it isn't repeated here as established fact. "No competitor product reviewed offers a comparable hub-mounted sensor" is accurate and checkable. "World's first" is a claim only iCheckTPMS itself has made.
It's also worth giving credit where it's due. TST's approach isn't nothing. A delayed, inferred signal is still a signal, and for an owner with no bearing monitoring at all, TST's early-warning framing genuinely does provide some advance notice compared to running no system whatsoever. It just inherits the same fundamental limitation every valve-stem system does: it's reading the tyre, not the bearing, so whatever it reports has already been filtered through however long it takes heat to travel from hub to tyre.
The Wheel Bearing/Hub Temperature Sensors are sold as an add-on, from $178 AUD, in a 2-sensor pack for single-axle caravans or a 4-sensor pack for dual-axle setups, and they pair with iCheckTPMS's existing IC008 and IC010 monitor kits. For anyone already running an IC008 or IC010 for tyre pressure, it's an extension of a system already in place rather than a second gadget to manage: one monitor, one display, tyre and hub data side by side.
Cost is worth putting in perspective too. A 2-sensor pack starting from $178 AUD is considerably less than a single roadside tow-and-recovery call-out after a bearing seizes somewhere remote, and a fraction of the cost of a wheel and hub assembly replacement plus the accommodation and delays that come with being stranded mid-trip. It's not a decision that needs much justification once you've priced out what the alternative actually costs.
Fitting the sensors doesn't require pulling the hub apart or any specialist tools beyond what a caravan owner comfortable with basic maintenance would already have on hand, since they mount externally rather than requiring access inside the bearing assembly itself. None of that replaces the value of a proper service on schedule. It just means the caravan is being watched in the months between services, rather than left to hope nothing's gone wrong until the next scheduled check.
What to Look For Before You Buy
If you're weighing up bearing monitoring for your own caravan, a few practical questions are worth working through before buying anything.
Start with axle configuration. A single-axle caravan needs a 2-sensor pack; a dual-axle van needs the 4-sensor version to cover both hubs on each side. It's a simple check, but it's also the first thing to confirm, because a mismatched sensor count means one hub going unwatched.
Next, ask whether the system you're looking at actually reads while the caravan is stationary, not just while it's rolling. Some tyre-pressure systems, and by extension any bearing-adjacent reading built into them, only take meaningful readings once the vehicle is moving above a certain speed. That's a real limitation if a problem develops while the van is parked at a caravan park for a few weeks between trips, since nothing would catch it until you're back on the road and already underway. Systems that check in on a fixed schedule regardless of motion, the way InstaData™ does every five minutes, don't have that blind spot.
Check, too, whether hub temperature shows up on the same display as everything else, or whether it needs a separate app, a second screen, or a different login to check. A second thing to remember to look at is a second thing that eventually stops getting looked at. One monitor showing tyre pressure, tyre temperature, and hub temperature together is a meaningfully lower-friction setup than juggling two systems.
It's also worth checking how the sensors are powered and how long that power lasts before needing attention. iCheckTPMS's sensors, including the hub temperature units, run on user-replaceable CR1632 batteries rated for roughly 12 to 18 months depending on use, the same battery already used across the rest of the IC008 and IC010 range, so there's no separate battery type to keep spares of. A system that needs an unusual, hard-to-find battery is a system that's more likely to end up ignored once the battery dies.
None of this replaces choosing the right base TPMS kit in the first place: sensor count, coverage for your specific axle and spare-tyre setup, and the features that matter for how you tow. iCheckTPMS's buyer's guide covers that broader decision in more depth, including how to size a kit for a single-axle van, a dual-axle setup, or a 4WD-plus-caravan combination. Bearing monitoring is worth thinking about as a genuine add-on to that decision, not a replacement for getting the base kit right first, and it's most naturally added at the same time as the primary TPMS kit rather than retrofitted separately later.
For anyone setting up a new system from scratch, it's worth looking at bundle pricing rather than buying components separately. iCheckTPMS's current Bundle Deal pairs the IC008 kit with a Signal Booster and Wheel Bearing Sensor for $549 AUD, a saving of $113 AUD against buying each piece on its own, which makes sense for anyone who already knows they want hub monitoring alongside standard tyre coverage rather than deciding on it later.
Finally, remember what monitoring is and isn't. It's not a substitute for the 10,000km/12-month service interval, and it won't fix a bearing that's already failed. What it does is tell you something's wrong while you still have options: pull over, check it, call for help before a slow problem turns into an expensive one.
Frequently Asked Questions
What causes caravan wheel bearing failure?
Most caravan wheel bearing failures come down to lubrication problems: too little grease, the wrong type, or grease that's broken down or been contaminated by water getting past a seal. Overloading, rough roads, and ordinary fatigue after enough kilometres account for most of the rest. All four causes eventually show up as the same symptom: rising heat at the hub.
How do I know if my caravan's wheel bearing is going bad?
The classic signs are a grinding or humming noise from the wheel, a wobble you can feel through the tow ball, or a hub that's noticeably hot to the touch after driving. The problem with all three is timing: by the time any of them are noticeable, the bearing has usually been degrading for a while already, which is exactly the gap continuous hub temperature monitoring is designed to close.
Can a wheel bearing fire actually happen?
Yes. The US National Highway Traffic Safety Administration has issued federal safety recalls, including 23V-230 and 23E057, over hub bearing systems that could overheat, seize, and cause a wheel-end fire or a wheel separating from the vehicle. It isn't the most common cause of a caravan fire (cooking appliances and electrical faults both rank higher, per RAC WA), but it's a real, physically documented failure pathway.
Can a standard TPMS detect a bad wheel bearing?
Not directly. A standard tyre pressure monitoring system reads temperature at the valve stem or inside the tyre cavity, not at the hub, so it has no direct view of bearing temperature at all. Some systems, like TST's, treat unusually high tyre-side readings as an indirect early-warning sign of possible bearing or brake trouble, but only a sensor mounted at the hub itself measures bearing temperature directly.
Does a hot wheel bearing always mean it's about to fail?
Not necessarily. Bearings run warmer after sustained highway towing or on a hot day, and some elevated temperature is normal operating behaviour rather than a fault. What matters is a temperature that's unusually high compared to the other wheels, or one that keeps climbing rather than levelling off. A monitoring system that shows all hub temperatures side by side makes that comparison straightforward; a single reading in isolation, without something to compare it against, is much harder to interpret on its own.
How often should I check or re-grease my caravan's wheel bearings?
Standard Australian guidance is every 10,000km or 12 months, whichever comes first, tightening to 5,000km or 6 months for heavy or off-road towing. A single extended trip like the Big Lap can cover two or three of those intervals in one go, often in remote areas far from a workshop.
Is TPMS mandatory in Australia?
No. There's no Australian Design Rule requiring tyre pressure monitoring on passenger vehicles, 4WDs, or caravans, so fitting one is a voluntary safety choice rather than a legal requirement. The US mandates TPMS on new passenger vehicles under the TREAD Act, and the EU requires it on new commercial trailers, but neither rule applies to private caravans in Australia.
Does iCheckTPMS's wheel bearing sensor work with my existing TPMS setup?
Yes, for owners running an IC008 or IC010 kit. The Wheel Bearing/Hub Temperature Sensors are an add-on that displays hub temperature on the same monitor already showing tyre pressure and temperature, rather than requiring a separate screen or app.
What's the difference between iCheckTPMS's bearing monitoring and other brands' claims?
Some competitor systems, TST among them, use a delayed signal read from the tyre valve stem as an indirect warning sign of possible bearing trouble. iCheckTPMS's Wheel Bearing/Hub Temperature Sensors are a physically separate unit mounted at the hub itself, measuring bearing temperature directly rather than inferring it from the tyre several steps removed.
