Can anyone ID this transmission for me?....Appears to be cast with 85217-27.....Thanks for any help...Mac
My neighbor just put one of those behind a hopped up 215 Olds. He said those transmissions require a bunch of know how to get them to work correctly, he's a smart guy.
Yes, my friend had one in and out and back to the pro rebuilder 3 times before it worked. Soon after sold the car
They're definitely a strange creature. The torque converter (or fluid coupling, or whatever it is) is internal.
The earlier Pontiac was the Hydra-Matic I believe.....which was the basis for the B&M Hydro etc?.....this one definitely sounds like a step backwards.....
I believe it was called a driven taurus. I think the converter was still in the bellhousing I think that driven taurus was second gear. I think??? I overhauled one years ago.
I saw one be removed from a '61 Pontiac, and the front of the transmission just had a splined shaft that went into a sort of clutch disc looking apparatus that was bolted to a solid flywheel.
It's bad when you get a Wikipedia shout out Roto Hydramatic (sometimes spelled Roto Hydra-Matic or Roto-Hydramatic) was an automatic transmission built by General Motors and used in some Oldsmobile, Pontiac and Holden models between 1961 and 1965. It was based on the earlier, four-speed Hydramatic, but was more compact, providing only three forward speeds plus a small 8" fluid coupling with a stator inside of the fluid coupling (a type of torque converter, only integral with the transmission rather than being an independent unit). Oldsmobile, one of the companies that used this transmission in some of its cars, called the fluid couplings stator the "Accel-A-Rotor." The lightweight, aluminum-cased transmission was sometimes nicknamed the "Slim Jim." HydraMatic Division calls the Roto a four-range, three-gear HydraMatic. It counts the stator multiplication at 3.50:1 as a first gear, and when road speed and the two coupling halves’ speed match, it counts the same gear with fluid now passing straight through the stator as 2nd gear at 2.93 to one. Second gear (or third range) has a ratio of 1.56 , and because the fluid coupling is drained for this gear ratio, making the front clutch apply makes this a rare automatic that is in FULL mechanical lock-up (coupling drained) in second gear. Fourth range the coupling fills, releasing the front clutch makes a ratio of 1 to 1. This transmission, like single and dual range and dual coupling hydramatics, also has the feature of split torque in the transmission, whereby in fourth (or high) gear only 40% to 50% depending on transmission—-40% in Roto's case—-but because of the design the coupling is only required to carry 40% of the engine torque. The remaining 60% is in full mechanical connection, which made these Hydramatics the most efficient automatic until lock-up torque converter came into widespread use. Roto's disadvantage was the 2-3 range or 1-2 gear change because it is not only a huge ratio jump from 2-3 range or 1-2 shift from 2.93 to 1.56, but also there is no fluid slippage in the coupling because the coupling drains (four-tenths of a second) to engage or apply the front clutch and so the trans goes to full mechanical connection. The other disadvantage of Roto HydraMatic was the extreme oil pressures in the small 8" fluid coupling, which caused transmission leaks. All HydraMatic transmissions suffer some shift quality with today's ATF fluid. The original "Type A" fluid that these transmissions take is available only at O'Reilly Auto Parts. There were two models of the Roto Hydramatic: the lightweight Model 5, which weighed 145 lb (66 kg) and had ratios of 3.03, 1.58, and 1.00, and the larger Model 10, which weighed 154 lb (70 kg) and had ratios of 3.50, 2.93, 1.56, and 1.00.
We don't talk about automatic transmission here. I thought you guys knew that? If you have an automatic, chances are there isn't a man in your family. They are for girls. Men have 4 speed transmissions. Or S10 transmissions, installed in cars that can't be driven very far from home, if at all. So let's review. Put a manual transmission in your car, don't drive it very far from home, if it'll even run that is, and make fun of those that drive the hell out of their car that has an auto transmission. Check. Got it? Good! As you were, pussy's
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