[PonchoTom6062]

I'm looking to swap out my Slim Jim tranny from my '60 Ventura for a Hydromatic. Is this an easy swap or will there be a need to get a custom cross member and other pieces? Thanks as always!

[poison heart]

If it's a 60 it should already be a hydramatic. Unless you mean swap out your hydramatic for a turbo hydramatic

[PonchoTom6062]

The current trans is a 2 speed auto. I want to replace it with the 4 speed auto, which I take is the turbo hydro. Would you know if this is a bolt in replacement or is modification required? Thanks again!

[poison heart]

You must be mistaken unless it's been converted. Is the motor the original motor? If it's the original trans it's a 4 speed auto matic (Hydramatic) which is the only transmission that is a direct bolt in. If someone has converted to a power glide or a superturbine or something then it would not be hard to convert to a 3 speed auto (turbo hydramatic AKA TH350 or TH400) which might be a better choice because they're easy to find and easy to find parts and cheap to fix. If it's a Hydramatic 4 speed then you will need an adapter to swap the tranny with a more modern tranny. The hydramatic 4 speed is the only auto tranny that will bolt to a 60 block.

I believe slim jims came out in 61 or 62 and they're 3 speed autos and from what I hear they are complete junk. I think the TH400 3 speed auto came out in 64 or 65.

A lot of people see D1 and D2 and think it's a 2 speed when actually it's a 4 speed. Same with the Ford Cruise-O-Matics. 2 Drive ranges but were actually 3 speeds. Same with Buick Dynaflows, people call them 2 speeds but they don't have any gears at all.

[PonchoTom6062]

I must have been given some bad info when I got the car. It was reported to be all original but the owner kept saying slim jim for some reason.

On another note, I just wanted to say THANKS to everyone on this website. I have received more valuable info here then anywhere else. Pontiac cars are fantastic and their owners even better!

[poison heart]

A lot of people mis ID those trannys.

Sounds like you have a 4 speed hydramatic. If you don't and you want one, I have a good one I can sell you. Or if you want a good slim jim I can sell you one of those for real cheap haha

This site is definitely the best Pontiac site

[Jack Gifford]

Ask Don Bennett of Texas if the RotoHydramatic was "complete junk". He raced a slim-Jim-equipped Pontiac very successfully back in the day- '62 & '63 I think- had some NHRA Nationals wins.

[poison heart]

OK, one guy raced one and had success vs 100s on here that hate them.

[stevep]

Not many people had good luck with Slim-Jims, especially up here in the Northeast. Slim Jims do not like cold weather. The torus bowl would always crack on a cold day.

[60man]

A Slim Jim will not bolt to a 60 Block ??? 61 bolt pattern is different..

[Jack Gifford]

Originally Posted by poison heart

... vs 100s on here that hate them.

... gotta go take my meds... feel an attack of Wikiphobia coming on...

[U47]

Originally Posted by poison heart

You must be mistaken unless it's been converted. Is the motor the original motor? If it's the original trans it's a 4 speed auto matic (Hydramatic) which is the only transmission that is a direct bolt in. If someone has converted to a power glide or a superturbine or something then it would not be hard to convert to a 3 speed auto (turbo hydramatic AKA TH350 or TH400) which might be a better choice because they're easy to find and easy to find parts and cheap to fix. If it's a Hydramatic 4 speed then you will need an adapter to swap the tranny with a more modern tranny. The hydramatic 4 speed is the only auto tranny that will bolt to a 60 block.

I believe slim jims came out in 61 or 62 and they're 3 speed autos and from what I hear they are complete junk. I think the TH400 3 speed auto came out in 64 or 65.

A lot of people see D1 and D2 and think it's a 2 speed when actually it's a 4 speed. Same with the Ford Cruise-O-Matics. 2 Drive ranges but were actually 3 speeds. Same with Buick Dynaflows, people call them 2 speeds but they don't have any gears at all.

First, both automatics were called hydramatic(by Pontiac) and both hydramatic's have the same shift indicators (PN'D'LR) . The difference is in Roto L is first, DR' is second and 'DR is third. In Super Hydramatic L is 1st & 2nd, DR' is third and 'DR is fourth. When Super Hydramatic first came out, 1956 in StarChief (860's and 870's continued to use the old "D" type dual range for 56) it was called Stratoflight also known as P type or P315 by Cadillac or Jetaway by Olds. From 1957-1960 Super hydramatic was Pontiac's only automatic, in 1961 Pontiac offered two automatic's. Super hydramatic in Star Chief and Bonneville and Roto in Catalina, Ventura and later Grand Prix. 1965 all the big Pontiac's got the T-400. ALL Oldsmobile's models changed from the Jetaway to roto from 1961-1964. Cadillac was the pioneer for the Turbo 400 as some of their models got it in 1964 and the whole line get's it in 65 like all the divisions. The hot tip for Pontiac engines (full size Pontiac) with trans mounted starters is to use the 1964 Cadillac Turbo 400 because it's the only T-400 with bellhousing mounted starter. There were two versions of ROTO Hydramatic, one for the full size Catalina,Ventura, G/P and all large Olds, and a SMALLER Rotor Hydro for the 61-63 F-85, Cutlass, and Turbo Charged F-85 Jetstar.
FYI Roto Hydramatic is based on SuperHydramatic 4 speed and both trans use the fluid coupling (drain and refill application) as a replacement for the forward clutch in the typical sense. A misconception by many is that the Roto has a torque converter. This is not true, it is still a fluid coupling with a added feature of a fixed stator (Olds calls it Accelerator) to multiply torque, but it is still a coupling.

Don

[poison heart]

Ok jack. Do a search and find me one post where someone is giving praise to the slim jim. And while you're trying to find just one, you'll stumble across dozens of threads of people have problems with them and converting their cars away from the slim jim. Certainly, no one is converting their cars TO a slim jim.

Yes, 61-64 is different than 55-60

[U47]

Robert, interesting note that especially Pontiac people have problems with Roto. Super Hydramatic and Roto are very sensitive to adjustment and have to be set to very tight standards to work well. Seems most people (and tech's) have a hard time with these fine adjustments. Roto is hard to get right on a tired engine/ or trans too. I collect Pontiac and Olds and in the Olds camp you don't hear much grumbling about this trans. This is probably because the people in the Olds camp that collect cars that have that trans don't drive their cars the way a Pontiac driver would do. The go fast Olds guys are either the real early guys 1949-1957, or the later 64- early 70's 442 guys so they miss that trans altogether. I'm not saying there isn't the odd guy out there with a 1962 394" Starfire out there going fast, but they haven't the same intentions with the car as I do with my 62 catalina.
I really don't know why Pontiac used the Roto except to save money and try to get a softer shift I remember my cousin bought a new 64 G/P and I thought that trans was pretty sloppy compaired to my 4speed Hydro in my 59 catalina. Later we were able to adjust his trans ( and still later modify ) to shift harder.
I made a mistake in my last post as I said Pontiac made two automatics in 61- 64 years actually they offered three, Super Hydramatic Star Chief and Bonneville, Roto for Catalina, Ventura, and later G/P and, Tempestorque for Tempest 61-63 and Super turbine 300 for 64 Tempest. Also that smaller version of Roto that went into 61-63 F-85, Cutlass, and Jetstar Turbo also went in some cars in the UK and Australia.
It's funny how these transmissions came about. On the old dual range (like B&M used) the 1-2-3-4 shifts would tear your head off and the public didn't like that. So the SuperHydramatic was designed to smooth this out by eliminating the forward clutch by instead using a fluid coupling to become the forward clutch (roto does the same thing except uses a torque mutiplyer to the coupling and by this eliminates the super low 3.96 first gear. The Roto is OK on breakaway in first gear because of the stator giving torque multiplication, but gets in the way of the coupling in high gear. This very same defeciency is also present in every car with a torque converter, although a T-400 with a switch pitch stator trys to eliminate the problem by going flat ( trying to make it work like a coupling ) in high gear cruise.
Unknown to some is the 4 speed SuperHydrmatic was the most effecient auto trans in the cruise HWY mode until the lock-up Hydrmatic's like 2004R and 7004R

Don

[65FATCAT]

So a 64' caddy t-400 can bolt up to a 61' - 64' pontiac without issue?

[U47]

I think there might be, but not sure of a flexplate issue. These are hard to find trans because they were used only in one model. They are all long tail shaft. Same bellhousing bolt pattern though. I know a guy who's got one in his 64 catalina. If I had a 64 Cat I would use the 4speed Super Hydro. Better yet a conversion to B&M hydro 4 "D" type.

Don

[Bill Hanlon]

Originally Posted by U47

Unknown to some is the 4 speed SuperHydrmatic was the most effecient auto trans in the cruise HWY mode until the lock-up Hydrmatic's like 2004R and 7004R

Don

I'd argue that a properly adjusted dual-range Hydra-Matic was locked up anytime you were in 3rd or 4th gear.

[poison heart]

That's good to know if that would actually work...

I would think the bolt pattern would be different though.

[stevep]

Originally Posted by 65FATCAT

So a 64' caddy t-400 can bolt up to a 61' - 64' pontiac without issue?

A 64 Caddy THM 400 was actually a Buick Nail Head trans with an adapter plate to bolt to a Caddy only bellhousing configuration. A 65-67 Caddy trans used their own Caddy specifica trans case. A 68-up Caddy trans will bolt to a Pontiac, Olds or Buick BOP pattern motor.

[stevep]

Originally Posted by Bill Hanlon

I'd argue that a properly adjusted dual-range Hydra-Matic was locked up anytime you were in 3rd or 4th gear.

How so?