Thiokol Snowcat Project

Snowy Rivers

Well-known member
Pretty well have to use the planetary axle for steering.
Others have used a standard diffy ...and used the brakes to lock up one track or the other.

I thought about that but then thought better of it.

The OC-12 is nearly bullet proof.

If you get the diffy all the way down and go through it you should be fine,

Now you did have issues with some breakage on the R&P if I remember correctly ??????

The biggest part of the OC-12 is keeping them in good shape.....
Once thrust washers and things start wearing out and junk goes through the gear and can and will get ugly.....

Water getting in....RUST ruins bearings then they grind themselves to bits and shed all sorts of metal scrap.

When you get ready to do the diffy...let me know, and we can come up and give you a hand.

I made several special tools to deal with the big box
I should have asked if there was a trick to getting this tranny back in by myself, as there isn't room in the cab for even one extra person. I ended up strapping the back of it up to the hand-rail and starting a couple long bolts, then just wrestled with it while basically standing on my head for a few hours. But the freshly rebuild NP435 is in and bolted down! Tracking down brake shoes and springs for the emergency brake was less than fun, but a local Potter Webster supplier found what I needed! Now for the Overdrive contraption! New Axle should be on it's way Monday, so I have about a week to get this all bolted together enough to move it up by the shop. Then the real work starts on the final drive, and repairs to the tracks.


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