Wheel Bearings on 91 Summit

I'm presuming the problem is front wheel bearings. The most common reason for premature wear is dirt getting in. This happens when the (surely new) oil seals can't do their job adequately because the sealing surface on the CD axle stub is worn or grooved.

Second reason is inadequate cleaning of the knuckle inside, such that the bearing outer does not exactly sit flat. This creates a distorted bearing that will wear quickly.

Third reason is that the knuckle itslef gets slightly distorted when the old bearing is pushed out, See above.

Last reason is inadequate lubrication. Some bearings are prepacked, others need cleaning and packing with the correct hiogh temp grease.

Stewart DIBBS

Thanks for your suggestions. It is both front and rear bearings that are wearing out prematurely. Next time I have them replaced I'll mention the above ideas to the mechanic.

John

Rears TOO? If its the same mechanic who has been replacing them each time, I'd get another mechanic.

91 rear bearings are twin tapered rollers, have to be PACKED with grease, and assuming a new seal is used too, it should last for years. If a bearing is assembled with minimal grease ie just a smear like I seem sometimes, its going to heat up and wear out. Maybe it will last 12 months or so, then its the labour to fix it all again. Good for repeat business, bad for the car owner.

Maybe your mechanic is not dishonest, just incompetent.

Stewart DIBBS

It did occur to me that the mechnics where my car was being repaired might be doing something incorrectly and I'm planning to try someone new next time.

Thanks for your advice.

John