65 3 on the tree with over drive ?'s

[luvbowties]

Originally Posted by j_lee223

Great luck, do you know what trany that is or if that OD can bolf to my stock 3spd thanks

Lee, GM's overdrives are complete transmissions not add-on-to-the-end units. Any overdrive from 1955 thru approx. 1969 should be roughly a bolt-in for your truck. (Among these, the earlier were non-synchronized in 1st gear, just like your orig. trans. The latter-year ones were fully-synch'd.)

I've used std. 3-speed floor-shifters and they fit the o/d trannies just like the non-overdrives. I feel sure one would conform to your stock, on the column shifter--maybe have to slightly bend a rod or two, yet maybe not even that.

Your biggest problem would be in finding one; and I'd suggest you find a complete unit/system, as parts are difficult to find. Should you be fortunate enough to locate one, installed correctly it would make for a sweet-operating vehicle.

It has a 70% gear reduction, meaning it would alter final drive of a 4.11 to a 2.88 (The math: 4.11 X.70 = 2.877). Gives best of both worlds, giving 4.11 to get going and 2.88 for cruising above 30 mph--that's approx. where the centrifugally-actuated governor allows driver to engage the od. [You could engage it in any gear so long as the engine would sustain such rpm's to go that speed!] Vehicles with that tranny generally came with a 4.11; altho' it would prolly work fine w/a 3.73--but anything numerically lower would likely lug your engine.

Hope this gives you a little insight into the GM 3-speed overdrives. They look just like the one that slorio led you to.
sam

[frankslagoon]

Originally Posted by luvbowties

Lee, GM's overdrives are complete transmissions not add-on-to-the-end units. Any overdrive from 1955 thru approx. 1969 should be roughly a bolt-in for your truck. (Among these, the earlier were non-synchronized in 1st gear, just like your orig. trans. The latter-year ones were fully-synch'd.)

I've used std. 3-speed floor-shifters and they fit the o/d trannies just like the non-overdrives. I feel sure one would conform to your stock, on the column shifter--maybe have to slightly bend a rod or two, yet maybe not even that.

Your biggest problem would be in finding one; and I'd suggest you find a complete unit/system, as parts are difficult to find. Should you be fortunate enough to locate one, installed correctly it would make for a sweet-operating vehicle.

It has a 70% gear reduction, meaning it would alter final drive of a 4.11 to a 2.88 (The math: 4.11 X.70 = 2.877). Gives best of both worlds, giving 4.11 to get going and 2.88 for cruising above 30 mph--that's approx. where the centrifugally-actuated governor allows driver to engage the od. [You could engage it in any gear so long as the engine would sustain such rpm's to go that speed!] Vehicles with that tranny generally came with a 4.11; altho' it would prolly work fine w/a 3.73--but anything numerically lower would likely lug your engine.

Hope this gives you a little insight into the GM 3-speed overdrives. They look just like the one that slorio led you to.
sam

Bowtie. are you running power thru the gov. and then over to the sol. I thought the gov. grounded the relay and then the power came thru the relay to the sol.