Has anyone here reset the gear lash on the pinion and ring gear in the rear diff?

[Deadly BlaZe]

Ok i've searched and searched but found nothing.

I recently changed the bearing on the drive pinion in the rear differential. I put it back together but I never reset the gear lash to oem specs. Has anyone here ever done this or know how to at all? I know that the service limit is 7 mm but besides that, I couldn't find anything. This seems to be a very rare problem among DSM'ers.

 

[steve]

It's not that excessive backlash in the rear diff is rare but that rebuilding them is.

The FSM has the procedure for shimming them and checking the teeth mesh pattern.

Steve

 

[Deadly BlaZe]

It's not that excessive backlash in the rear diff is rare but that rebuilding them is.

The FSM has the procedure for shimming them and checking the teeth mesh pattern.

Steve

Where can i get that manual? From the dealer? And do you know if driving it with the back lash is bad for the rear diff?

 

[steve]

Brand new from the dealer, used off eBay, on CD from www.manualcd.com

 

[Deadly BlaZe]

Brand new from the dealer, used off eBay, on CD from www.manualcd.com

Thanks just bought the cd. Do you know if it's bad to drive the car with the wrong lash?

 

[Defiant]

Other than main and rod bearings, the ring and pinion mesh adjustment might be the most crucial adjustment on a car. It's not a trivial job; it takes at best, three complete assembly and disassembly processes to get it set correctly. Good luck finding the pinion adjustment shims. It's such a knack-intensive job with such dire results (hideous whining, at the least) that it's usually left to specialty shops that do little else.

 

[Deadly BlaZe]

Other than main and rod bearings, the ring and pinion mesh adjustment might be the most crucial adjustment on a car. It's not a trivial job; it takes at best, three complete assembly and disassembly processes to get it set correctly. Good luck finding the pinion adjustment shims. It's such a knack-intensive job with such dire results (hideous whining, at the least) that it's usually left to specialty shops that do little else.

Well i Just bought the factory service cd manual there's lots of info on how to do this. Now I just need to see how to get this right. On a side note, I did get the shims, spacer, and both bearings for the pinion from the dealer. Does anybody have any info at all on how to do this? Have you ever done this Defiant? If not, can you at least give me any info from what you know? Also, if I end up getting it wrong again and just decide to drive it how it is, will my differential eventually be blown to pieces?

 

[GVR4592]

Theres a ton of info on how to setup differential on various 4x4 sites, I would try there. I really don't think many of us have ventured into that area because of the cost of tools and the specific experience it requires.

 

[Defiant]

Have you ever done this Defiant?

Jeeze, not me. Too scared.

If not, can you at least give me any info from what you know?

Not much more than assembling everything to full-torque, painting the gear faces with machinist's blueing, looking at the mesh pattern and disassembling and swapping shims as needed.

Also, if I end up getting it wrong again and just decide to drive it how it is, will my differential eventually be blown to pieces?

Maybe eventually. But the howling will probably drive you batty first.
Hell, if you're that interested, you may have the knack the job needs. Then again, you might be a concert violinist, if you'd ever try that.

About the same odds, I'd say.

For me, diffs are just too plentiful and too cheap.

 

[steel_3d]

If it's set too tight, ie zero lash, you might get into trouble. I'm pretty sure you can feel this by hand, though. You'd even feel it binding. If it's too loose, I would avoid a lot of hard decel followed by hard accel, cause slamming the teeth that way might break them. Otherwise I think it's fine to drive for a while.

Don't take this for granted, but as far as gear lash, I think you're fine as long as you can feel a tiny bit of play by hand, but not too much play. In fact I think even stock untouched diffs have quite a bit of play after 100k miles, yet they still work fine.

Now, has anyone tried rebuilding a transfer case? I think I'll rebuild mine since apparently the 97-99 t-cases are stronger than the older ones, but they're hard to find. It's pretty simple from what I can see by taking it apart, but I feel like I'll have to adjust gear lash too. Time to bust out the ####in manual.

 

[Deadly BlaZe]

If it's set too tight, ie zero lash, you might get into trouble. I'm pretty sure you can feel this by hand, though. You'd even feel it binding. If it's too loose, I would avoid a lot of hard decel followed by hard accel, cause slamming the teeth that way might break them. Otherwise I think it's fine to drive for a while.

Don't take this for granted, but as far as gear lash, I think you're fine as long as you can feel a tiny bit of play by hand, but not too much play. In fact I think even stock untouched diffs have quite a bit of play after 100k miles, yet they still work fine.

Well I finally got it set up. I did it so that there is a very small bit of play. There is still some noise at around 35mph and up, but not nearly as bad as it was before. Hopefully everything will be ok. I'll just blast my music and pretend like everything is ok...until i have to buy a new diff.