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Hi Folks,

Moving on from the block photo from a few days ago, here's the transfer case. Notice the gouges where the idler shim has spun. What's gone wrong? Is it repairable? Is the housing toast?


Regards, Liam.

You can machine the face and take thicker shims.

Done this serval times.

Can you post up a few photos of the Idler Gear so we can see the Axles on it ?

It can be saved as Fanfaniracing has said and shown, but if the alignment between the flywheel housing and the gearbox case is poor, then you can only expect more of the same until that alignment is corrected.

Thanks for your help guys. Can you double up on idler shims if the depth is too much?

Additional pics as requested. Note the chunk of Ali stuck to the outer shim.

Regards, Liam.

Thanks for the photos Liam.

Just based on what I see in them it looks like the Oil Film between the original thrust and the Alloy Case broke down and the Alloy picked up on the Thrust, once that happens, it's pretty much 'game over'. It may not necessarily be that the Oil is poor quality or not up to the job, the break down in the oil film can (and usually) comes from very high spot temperatures. These hot spots from my experience usually come about from something being out of alignment, or it could also be from a contaminate being picked up and mashed between the Case and the Thrust, though often, there's evidence of that, which I don't really see here.

Looking at the Idler Gear, I can see there's some misalignment between the Flywheel Housing and the Gearbox Case. I have seen much worse, usually in the later cases. While some Cases and Housings align better than others, I'm yet to see any that correct. The factory really would have been better off making this a dead axle and fit the baring on to that for the gear to spin on, then these misalignment would have far less an impact. I really can't say if the cause of your issue here was caused by the misalignment, maybe, maybe not, but it can't be helping at all. Regardless if you replace the Flywheel Housing or repair the old one, I would recommend aligning the Housing to the Case.

In regards to the thrusts, I doubt you'd be needing to add circa 0.125" of additional thrust thickness. The standard thrusts were made in thicknesses from 0.127 to 0.133". One or a pair could be ground down in thickness so you'd end up with a final total thickness you are needing, however they are only case hardened and you'd be well past that. As well as that, the Oiling groove would also likely be gone. I make my own here in 4140, though EN16 or EN18 or EN24 would be fine (originals are EN18), cut an Oil Groove, harden them and finally grind to the required thickness.

If you need them, guess-works has oversize thrusts in various thicknesses up to 0.146”

Thanks everyone!