Adding BUSHINGS / BEARINGS to output cups at center diff ( Both sides ) & Housings F & R

Big Kid

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On another post it was mentioned that GPM & Hot racing Diff housings did not have a steel insert at output cup hole and prone to premature wearing out (n)
Ok, lets fix that and also add even more toughness !!

Now having a small machine shop helps no doubt, but REASON for post is to show what can be done if really wanting / needing a tougher center differential and able to repair or retrofit any Diff housings (y)

In the lathe took a .250" reamer to the bearing side of housing going inward .225" ( This is shy of passing threw leaving the o-ring shoulder on inside undisturbed )
Next using PEEK ( An aerospace plastic for bearings & high wear applications ) making a small stub that was @ .002" oversize and pressed it in.
Next drilled it in the lathe with a .195" drill making a hole threw it where a drive cup just slips in. Nice fit !!
*Now you could do this with steel ( not recommended ) Bearing bronze etc ...

Checking hardness of a spur wheel decided it too could be reamed as well. Same type deal as housing.
Once assembled stretch a few o-rings over the cups that has a smaller one on first resting up against bearing inner race NOT TOUCHING seal, and 1 or 2 larger ones that has them under slight squish. This SEALS the drive cup output shafts keeping dirt & debris out and lube in.
* Original post on o-ring sealing here: Seal them outputs !

END RESULT is that the outputs cups have near zero run out / wobble and now having an actual bearing material rather than steel on steel should dang near last indefinitely.
Assembled 2 diffs with shim kits & fresh bearings .... Now have 3 diffs in total set up as such with Light / Medium / Heavy fluids.

Hope this helps or is of some use to you more serious bashers & hobbyists.

Scott
AKA: Big Kid

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morrjr71

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IMO, it's not worth the effort to try and upgrade GPM parts, which are of mediocre quality to begin with. Your time is worth money too, and I think if you count your labor cost into the overall cost of the GPM parts you will find the GPM parts will be more expensive than better quality parts from manufacturers like M2C, Basher Queen, Scorched, and others. The old saying "Buy once, cry once" applies to drivetrain parts.
 

Big Kid

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IMO, it's not worth the effort to try and upgrade GPM parts, which are of mediocre quality to begin with. Your time is worth money too, and I think if you count your labor cost into the overall cost of the GPM parts you will find the GPM parts will be more expensive than better quality parts from manufacturers like M2C, Basher Queen, Scorched, and others. The old saying "Buy once, cry once" applies to drivetrain parts.
I'm retired and been a hobbyist for many many years.
Was given the new diff housings .. so out nothing.
Take the post as a novelty if you wish :cautious:
 

morrjr71

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I'm retired and been a hobbyist for many many years.
Was given the new diff housings .. so out nothing.
Take the post as a novelty if you wish :cautious:
It’s all good if you have the time and tools and you got the parts for free. I was just pointing out that upgrading GPM parts isn’t for most people, especially for hard core bashers.
 
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