Rebuilt gearbox noise when spun by hand

[pnikas]

Originally Posted by jess p

The cage on the drive shaft in the intermediate plate of my trans was broken in 3 places. I replaced both bearings. I placed the intermediate plate in the oven After removing the steel retaining cover to remove the outer races. Heated the plate up again to drop in the new outer races. Now as I read you left the shift forks on both shafts with their respective shift rods while you tended to the bearing issues. That sounds very difficult to do, that’s why I had the jig. OK, as I mentioned you had some playing around to do when switching the ring gear and the small spacer. I’ll go back and watch again all three YouTube videos and try to hear the noise. But as you mentioned the noise is most noticeable previously when you had it in 4/5 gear.

I think so too, could it be that some bearings are running dry?
The outer race came out of the race relatively easy compared to the new. The new required some heating of the plate.

[pnikas]

Originally Posted by jess p

The cage on the drive shaft in the intermediate plate of my trans was broken in 3 places. I replaced both bearings. I placed the intermediate plate in the oven After removing the steel retaining cover to remove the outer races. Heated the plate up again to drop in the new outer races. Now as I read you left the shift forks on both shafts with their respective shift rods while you tended to the bearing issues. That sounds very difficult to do, that’s why I had the jig. OK, as I mentioned you had some playing around to do when switching the ring gear and the small spacer. I’ll go back and watch again all three YouTube videos and try to hear the noise. But as you mentioned the noise is most noticeable previously when you had it in 4/5 gear.

I just found where it’s coming from , I loosened half a turn the diff housing bolts and the rumble stopped , I installed new diff bearings , so the possibilities are
1) too Much preload
2) little backlash (shouldn’t change though with half a turn on the cap
3) I messed a bearing (most possible )
4) bearings have to work a bit ?

[pnikas]

I set the preload wrong . Dumb me .
Should I adjust it with a paper gasket at the diff cover ,

[jess p]

No paper gasket comes with the diff cover, only that big rubber O-ring. If you pull the diff cover out very much, I know the paper gaskets come in very thin sizes and it should not leak. Are your diff. races seated well? Are you able to obtain different spacers?

[jess p]

Also take into account that when the case heats up the carrier bearings are steel. You have a film of oil and the case is of a different material thus different coefficients of thermal expansion.

[pnikas]

Originally Posted by jess p

Also take into account that when the case heats up the carrier bearings are steel. You have a film of oil and the case is of a different material thus different coefficients of thermal expansion.

I changed the thin shim to achieve proper preload . Installed it on the car and tested .
In general terms it is awesome . Shifts nice , stays in gear , the only thing I noticed it a slight noise when taking foot of the gas pedal , it’s more noticeable when cold . Camera can’t catch it since the engine covers it