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I am having a really hard time figuring out what this transmission is.

It come off a 64 Bonneville.

I think it is a Hydra-Matic 315 transmission. But Someone told me it is a GM Roto Hydramatic transmission.

I know I know, The bell housing is smashed. The guy I got it from could not separate it. So he smashed it with a hammer. He still did not separate it. I got it like this.

Anyway if anyone knows what it is I would appreciate it. He told me it was a heavy duty transmission and people liked them for ls2 conversions because they handled torque real well. But 3 of the 4 things he told me were a lie so I duno
 

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I am having a really hard time figuring out what this transmission is.

It come off a 64 Bonneville.

I think it is a Hydra-Matic 315 transmission. But Someone told me it is a GM Roto Hydramatic transmission.

I know I know, The bell housing is smashed. The guy I got it from could not separate it. So he smashed it with a hammer. He still did not separate it. I got it like this.

Anyway if anyone knows what it is I would appreciate it. He told me it was a heavy duty transmission and people liked them for ls2 conversions because they handled torque real well. But 3 of the 4 things he told me were a lie so I duno
Yep, looks like the older 1964 and under Hydramatic. Has the 2-piece torque converter/ring gear. They were the common trans in GM cars. My first car, '56 Pontiac, had the Dual-Range Hydramatic and these were 4-speeds with a 1:1 4th gear. Made the cars very fast even though smaller cubic inch engines (316CI for the '56 Pontiac). Very heavy as they were cast iron. Pulled mine out to install a factory 3-speed/column shift from a donor car. It was fun but the trans was weak and started to give problems and then the clutch linkage finally gave up one day. So back in went the Hydramatic. Then it developed a leak/crack in the torque converter shell and a trans shop welded it up for me and I was good to go.

The Hydramatic was a popular trans with drag racers and B&M was one of the name brands who built them them for the drags. I had one, but never got to use it.

Check out this website as you can click on the transmission types and then take a look at the exploded parts as well. The Hydramatic, Jetaway 315, and the Roto-Hydramatic (known as the "Slim Jim"). The "Slim Jim" from all accounts I have heard was junk and did not hold up well to hi-horsepower or abuse. The pan is kinda odd looking and is different from yours, so it does not appear to be the Roto-Hydramatic. Click on this link: Early GM Transmissions
 
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