Bearing life question

[myredracer]

In pondering life and the universe, I am wondering if anyone can tell me why bearings on a trailer should be repacked at least annually?

Am curious because in comparison, bearings on cars and trucks can go for many 10s of thousands of miles and are okay. It can't be because the per wheel loading is higher than a car or truck. Is there something that drastically different about trailer bearings?

Need to be able to sleep again at night.....

[RanCarr]

Originally Posted by myredracer

In pondering life and the universe, I am wondering if anyone can tell me why bearings on a trailer should be repacked at least annually?

Am curious because in comparison, bearings on cars and trucks can go for many 10s of thousands of miles and are okay. It can't be because the per wheel loading is higher than a car or truck. Is there something that drastically different about trailer bearings?

Need to be able to sleep again at night.....

Lippert just replaced the bent axles on our TT with heavier ones and the bearings needed to be repacked. There's less than 3000 miles on the TT. Or is that normal when defective or inadequate axles give out?

[myredracer]

Another Lippert problem?? Lippert frame/axle/brake problems seem pretty common.... Just got our new trailer 2 weeks ago, and it was only one day old when we discovered that 4 of the 6 the spring hangers on the Lippert frame are bent to one side. Waiting to see what Lippert will do.

Anyway, I would say repacking the bearings anytime they have the brakes apart or axles out would be standard procedure. They are supposed to be redone annually or at 10,000 miles, whichever comes first.

We had the brakes on our last trailer replaced under warranty and they repacked the bearings, which we paid for as it was at about 15 months. We paid for that as they needed repacking anyway. Lippert agreed to warranty the brake repair, but it took over a year to get resolved.

[Caveman CBB]

Trailer bearings are built lighter and cheaper. That being said it is more about the miles in my opinion. I hardly ever go more then 50 miles from home and for that reason I get less the 3000 miles a year on mine. I only repack them every few years.

[bartlettj]

The annual repack is because you can't hear the bearings when they start to fail, so they want you to inspect them regularly. Most of the times bearings will make some serious noise before they start to become dangerous.

[TRAILERKING]

One thing with any trailer wheel bearing is they get a lot more abuse because of some of the "Extreme" side loading they can be subject to from tight turning. If you ever watch the wheels when doing any sharp turning, especially a jack-knife situation, you will see tires scrubbing and folding over, extreme changes in wheel camber just from the pressures exerted.

[450Donn]

If an angular contact bearing is packed properly it should run for many many thousands of hours without failure. There is IMHO no, zip, zero nada reasons to replace a perfectly good bearing with a new bearing unless it has become contaminated and damaged.

[TRAILERKING]

Originally Posted by 450Donn

If an angular contact bearing is packed properly it should run for many many thousands of hours without failure. There is IMHO no, zip, zero nada reasons to replace a perfectly good bearing with a new bearing unless it has become contaminated and damaged.

That's right......Usually just good to clean, inspect, repack & adjust.

[bartlettj]

Originally Posted by RanCarr

Lippert just replaced the bent axles on our TT with heavier ones and the bearings needed to be repacked. There's less than 3000 miles on the TT. Or is that normal when defective or inadequate axles give out?

If the axles were undersized for the trailer, then the bearings were too. Overloaded bearings will fail quickly.

[ralphie]

I've never truly believed annual bearing service is required and I generally do it every two years instead. I think a properly lubed and adjusted bearing set could go many thousands of miles without service, just like the ones we used to have on most of our autos.

[Shadowcatche]

As with many thing there are different grades of bearings, nine recognized. The bearings coming from where ever and not graded (all that I have seen) for trailers, lead me to think they probably tend to be at the lower end. Bearing Tolerances and Precision Levels | AST Bearings The other half of the equation is the grease used, synthetic preferred Grease selection One of the other purposes is inspection of brakes. When I do the inspection repacking of the brakes this spring I plan on, if possible replacing the Dexter bearings with, if possible, better quality bearings and seals and using Amsoil NLGI 2 grease.

[Pds47]

Trailers with out oil bath bearings are packed with grease and all trucks and cars have diffs and are lubed by oil.

[bartlettj]

Originally Posted by Pds47

Trailers with out oil bath bearings are packed with grease and all trucks and cars have diffs and are lubed by oil.

Actually, most cars use greased bearings, but they are usually factory sealed units now. For cars, most of the time the differential is a unit and then connected to the hubs by half shafts, and the non-drive axle doesn't use oil. For trucks, only the rear axle is oiled. The front has stub axles and half shafts with CV joints if 4wd.

[TRAILERKING]

Originally Posted by bartlettj

Actually, most cars use greased bearings, but they are usually factory sealed units now. For cars, most of the time the differential is a unit and then connected to the hubs by half shafts, and the non-drive axle doesn't use oil. For trucks, only the rear axle is oiled. The front has stub axles and half shafts with CV joints if 4wd.

Again refer to post #6.......Cars and trucks wheel bearings are not subject to the same abuse of the extreme "Side-Loading" like with trailers.