Diff maintanence/overhaul?

[MMoyle]

Howdy all,



I have 138k on my truck and the rear has been serviced it's entire life from the original owner. When should I consider overhauling the front and rear diffs? Changing wheel bearings, seals, etc? I would like to get on a schedule and just do it at certain intervals. For example, should I overhaul the diff every 120K or something like that? I would hate for it to bite me while crossing the steep grade into Jackson Hole Wyoming. Do you think this is a good schedule to get on? How much does a front and rear diff overhaul cost? I'm a novice when it comes to diffs..... Thaks Mike

 

[dan brooks]

I change the fluid once a year, just before vacation, and look everything over really good. Check for unusual debris on the magnet - a little paste-like collection is fine - and in the little sunken area under the ring gear (bigger chunks will collect here). If everything looks good, the diff makes no noise, and doesn't leak, keep on driving. Any problems will give you some kind of indication - in my case it was a couple shims stuck on the magnet. I had a cracked race in the front axle of my Jeep a few years ago and found a lot of metal slivers on the magnet.



As far as wheel bearings, I normally pack them and replace the seals once a year or if I have the brakes apart for any reason.



Overhaul cost depends on what parts are needed, but figure $250-350 labor per axle. You could easily have $1000 or more in the rear axle alone if the ring and pinion, all the bearings, the case needs be replaced. Any problems with the housing (spun races) will drive the cost up more.

 

[MMiller]

I recommend the backlash checked on the rear diff. My brother had my truck one evening at about 200,000 miles and removed 3 teeth from the pinion. It had no noise warning. I am thinking the backlash may have been a little loose. This is pretty consistant with the 70 rears on a high milage truck. I can't say he abused the truck, any worse then me anyways. :-laf



I too just repack the wheel bearings, and re seal on the front.



Michael