At AllBrand, we believe in the necessity to be meticulous when it comes to wheel bearings in your van. These are quite possibly the single most important aspect of your rig’s rolling platform, forming the link between the stub axles and the wheels of the van. And while the bearings in your tow vehicle’s wheels are quite large, the ones in your van are usually no greater than 2 inches across. Also, whereas the tow vehicle’s wheels share perhaps 1.5 tonnes between 4 or more sets of bearings, your caravan endures often approaching or exceeding 2 tonnes between them. Because of this incredible stress, bearings are placed under much greater stresses than the ones you’d be used to in your vehicle, and as a result need to be maintained especially well. In a road-going application, they’re subjected to the heat transfer from the braking components, general friction heat from rotating as much as they do, great rotational forces which can lead to issues if they’re incorrectly tensioned, as well as just general environmental factors. Also, because caravans stand for much longer periods than vehicles do (all the while carrying that aforementioned weight) they become target to things like flatspotting which can cause a rough or uneven ride. Ensuring they’re well greased (not too much, and definitely not too little) can help.
If you want to see the massive stresses at work in action, watch someone with a tandem axle van making a tight turn. The wheels actually begin to twist under the extreme strains. Imagine just how much force is being applied to those little rollers, all across the space of around 2 inches. When they finally fall victim to these stresses, it can be pretty disruptive to your holiday. Not only could it seriously damage your van, but just the hassle of having to be recovered from a potentially remote location simply is not worth it. This is why we pay such close attention to these vital, albeit small, components of your rig.
Here’s some things for you to think about when you next set off. Assuming the majority of vans run with 14″ tyres, we can deduce the following:
- At 100km/h, your rig will travel 1 kilometre in the space of 36 seconds.
- Your wheels, and in turn, your bearings will rotate 534 times in every kilometre driven.
- This equates to roughly 14.8rps, or revolutions per second.
- This is the same as 889rpm, or revolutions per minute.
On a decent trek, that’s a whole lot of turning you’re asking your bearings to do, especially under the weight you’ve got them carrying! Keep them fresh and keep yourself out of trouble.