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TR5/TR250 Trans swap

tinman58

Jedi Knight
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I have a TR250 with a 72 TR6 motor and trans with overdrive. The transmission is not in the best of shape. It growls and will pop out of 2nd gear while slowing down. In hindsight I should have gone thru the tranny while I was doing the restoration. The question is... I have a TR3 transmission that I could rebuild while still driving the 250.Could the TR3 transmission mate up to the TR6 Motor and overdrive? Or am I asking for trouble? What I want to do, is a weekend swap, no down time for the TR250.
 
You'd have to buy another mainshaft to match the OD & 3 synchro box. Besides, since they share oil and what you are describing sounds like the countershaft bearings and/or thrust washers have failed, you'll probably want to go through the OD as well. No sense hooking a freshly rebuilt gearbox to an OD full of crud.

I'm thinking the longer input shaft could be a problem, but don't know for sure. You'll probably have to cut down the front cover as well (although I'm told that depends on exactly which pressure plate you have). Oh yeah, and if it's from a pre-TS50000, the starter won't fit. I think you can get around that by using one of the "high torque" aftermarket starters, though.
 
Thanks Randall! I will rebuild the existing one it the 250. I will have to drive the TR3 instead.
 
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