Perfect backlash?

How important is it? Setting up my new gears, and can only get down to ~.012 with the shims I have, while spec is .005-.008. Also have a slight warpage of the ring-gear, but I believe it's a tolerable amount.

Gears had been run previously at a higher lash, as evidenced by the wear pattern, so should I get an install kit and get it perfect or just let it go?

i would keep trying to get it within spec

get more shims

What axle are we working on?

Are you saying you have "run out" on the ring gear? If so, it could be something as simple as a spec of metal between the carrier and ring gear. I would remove the ring gear and re-clean the 2 mating surfaces again. I also run a file over both surfaces before cleaning them to remove any burrs. You are going to have some run-out regardless but a little is ok.

BL should be in the specs. Too tight and they will bind as the gears heat up, too loose and you are making contact out on the thin side of the gears which will make them weak. Any ring gear deflection at all will make the contact surface smaller on the teeth so you need to keep it in spec.

Get more shims.

Yes on the runout...will pull it apart tomorrow and see what's causing it while re-shimming for lash.

X2 on running a file across the ring gear and carrier I do this on every set of gears I do you would be surprised how big of a difference it can sometimes make. If you need more shims try a shop that does gears and they should have extras they may give to you or sell cheap, I would give you some if you where near me.

Be warned tho..... shimming to the correct backlash may produce a slight gear whine. Mainly because you're running partially on "new" surface and partially on the "worn" surface.


It should have no affect on the life or reliability of the gear set. Just noisey.


1.5 - 2 thousandths run-out is acceptable and quite normal. 3 is borderline and would depend how close you can get to the proper backlash after you re-shim everything. What range are you seeing? If you remove the ring gear ... you may want to spring for new bolts as well. Use your dial indicator to determine the runout and then post it up before digging deeper. Might save you some time or effort.



Joe

Seeing about .004 runout so I'm going to pull the ring to see if I can determine what's causing it. Will put new bolts in it if I can correct the issue or just start over if not. If I can't save it I'll find an 8.25 instead of putting the $$ into this D35.

Thanks all!

JRW is right about running a file across the back face of the gear and on the carrier surface as well.


The bigger the file, the better.




Joe