rear end slack

[gmc89]

My 99 ford 350 diesel seems to have a lot of play or slack int he drive train.Even when i am pulling our camper 32 fifth wheel when slowing down to turn and then accelerating i can hear a clunk. All ujoints have been replaced and am thinking about doing the slip joint mod if this will fix it. My nephew who is a mechanic seems to think that the rear end gears need shimming, this is hard to believe when the truck only has 132.000 KL. on it.I did have the pinion seal replaced about a year ago.Any idea's.Thanks Tom

[klhansen]

I doubt that your rear end is worn that much. And if it is, you probably can't get away with just "re-shimming". Doing that will probably make it whine like a banshee, as it changes the gear mesh pattern from what has already worn into it. Could possibly be the side gears and differential gears worn, but again, unlikely.

Check it by pulling the driveshaft off the pinion yoke and check just the rear end.

My guess is that your slip joint is what's giving you the clunk.

[gmc89]

Thanks ,first chance i get if it does not get to cold i will pull the driveshaft.

[tattoocharlie]

i just fought this fight....i had recently greased my slip joint then shortly after developed the klunk.i replaced calipers(i did have one hanging up)checked rear end...i was pulling my hair out.i was experiencing a klunk when brake pedal was released,applied,under acceleration....i even had a surge when shifting into park.because i had recently greased my slip joint i dismissed it....then at very last i pulled my driveshaft and the slip joint was frozen....i had to hammer it apart.apparently the grease i used(a thick syn wheel bearing grease)so i switched to a red ep(extreme pressure)grease and whoila!!!!!!!!!!!!no more klunk...........hope this helps


by the way my truck has 218k....my rearend is still good....