1960 Willys Overland transmission rebuild.


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After finishing the front grill and front axle assemblies, I was curious to see if the overdrive system could be make to work. This vehicle is fitted with a Borg Warner 3 speed manual gear box, a T96 unit, with a R10 2 speed overdrive transmission on the back. It's a neat set up that includes a centrifugal switch than engages the overdrive transmission at about 29 mph. This reduces engine rpm's by about 27%. I focused on the electric solenoid first and got this all working properly. Once back in the vehicle properly, I installed a switch on the dashboard that would allow manual engagement of the overdrive unit. Taking it for a test drive, we discovered it simply would not go in OD, despite being able to hear  the unit click into action. Back at the house, we were unable to get the tranny back in reverse. So at this point I decided to just take the entire unit apart and find out what might be wrong. Surprisingly things were in great shape inside.

Here are all the parts to the 3 speed gear box removed and all cleaned up from the parts washer.

And here are all the parts to the 2 speed planetary OD gear box on the back of the regular tranny. One bad roller in the one way clutch mechanism was found, but that was it. Everything else looks great!

While were this far into it we decided to go ahead and remove the bell housing and look at the clutch. Once the bell housing was cleaned up it was blasted, taped off, and sprayed a shiny coat of Imron. Devin is spraying the black Imron paint with the small gravity feed spray gun.

New seals and a couple of bearings have been fitted, along with a replacement of the brass synchro rings and springs (good assurance to easy shifting) and things are going back together.


It's fun to turn the shafts with the covers off and see everything working inside.

Decided to go ahead and clean everything up that will be in contact with the freshly painted transmission. The flywheel was removed and the plate between the end of the engine and the bell housing removed, blasted and primed in self etching primer. Won't paint it black at this time, but rather will wait until painting the engine after rebuilding it. The same was done with the back U-V joint, drive shaft, and the shift rods.