Transmission questions

Just some questions for you old car transmission experts out there. (I know, I could do some research, but this way is more fun....)

My first car was a '63 Olds F-85 Cutlass coupe, with a 4-barrel 215 V8 and a 'hydramatic' (shifted from the column). To this day, I remember how smooth that automatic transmission shifted - really 'turbine-like'. I distinctly remember it shifting through 4 forward gears....

Couple of questions -
1. Was this basically the same automatic that went in the larger Oldsmobiles, or a 'junior' version?
2. Was this the same transmission that Buick used in their Special (Dynaflo)?

 

I really dunno but wanted to write something. Don't believe the Dynaflow was anything like the Hydramatic. I had many Dynaflow cars and remember them as two speed automatics that were smooth.
I did have one Olds with Hydramatic, a 1949 Olds 88. When it shifted there was a jerk in each gear. (No not me) I couldn't destroy that tranny when I tried before scrapping the car. Believe me I tried. But the Dynaflows self destructed when I didn't want them to!
Now that I look back I don't know why I junked the Olds torpedo back. I loved that car and wished I owned it today. From what I remember an old car wasn't worth anything on trade and no one else wanted it.
Okay, didn't help you a bit. :banghead3:

 

My junior league research(and trans knowledge) on the 63 F85 found they had what Olds called a RotoHydramatic auto trans. Not sure about how many forward gears. I remember my mom's wagon from that year was smooth shifting but seemed "slushy"(lots of hp loss) with that trans. I think it was a scaled down version of the trans used in the larger cars with the 394 V8's. Some people called them a "slim Jim" trans and apparently the innards were different enough to require someone with special training for overhaul.

 

Krash - I had the hydramatic in a few vehicles and it was four speed. The only one that shifted harsh was one we dicked with to get shifts we could really "feel". Before we played with, and the others, were all really decent tranny's. Tough, heavy, I'd have another in a car without worrying.

I believe the F85 had a smaller version of the Dynaflo. I know there was a slim jim trans in those years but thought it was only on the big cars with a stepped down version for the little cars. I'll ask some buddies who are really into the early 60's Buicks and see what they know.

I do know my buddy with a '63 Riv had the slim jim and I can't post on this forum his comments about it without getting punted, like he did the trans.

 

Here's a linky:

http://en.wikipedia.org/wiki/GM_Roto_Hydramatic_transmission

 

The F-85 had the smaller version of the Slim Jim. It was actually called the Roto Hydramatic model 5 or the RHM 240. The large 61-64 Olds and 61-64 Catalina/GP had the Roto Hydramatic model 10 or the RHM 375. The 61-64 Bonneville/Star Chief still used the Dual Coupling Hydramatic.

The Buick Special used the small Dynaflow called the Dual Path. The RHM 5 and the Dual Path could be intechanged between the Olds/Buick if you used everything. The RHM was better than the Dual Path. The Dual Path had only 1 bolt attaching the pan to the case.

The 63 Riviera had a Dynaflow. It was the last year that Buick used it.

 

Thanks for the info and links, guys....
Apparently I was wrong about it being a 4-speed.
Info also means it was the same transmission in my '64 Pontiac Ventura.

 

I spoke to my Riv buddy tonight. He has a '64, not '63. Oops. Slim jim is what he said it had, he punted that for a turbo 400 and is extremely pleased with the swap. He could not give the old tranny away, even to a trans shop, so it went to the metal scrap yard.

 

The 64 Ventura had the large Slim Jim. It did not share any parts except for the front seal.

 

A 64 Riv had a THM 400 in it from the factory, but it was a single range. The shift quadrant on a Dynaflow was "PNDLR" and a single range 400 was "PRNDL".

 

I just removed one from my 62 Catalina. I don't know why they call it a Slim Jim. The transmission is HUGE!!! If you shift through the gears there is 4 gear detents. The first gear is split. That was a nice feature, because a lot of the big cars had highway gears. 2 series. 2.42 or 2.73s. I was going to rebuild mine, but the parts are VERY hard to get. Then you have to find someone who knows how to rebuild them. I donated mine to a needy soul.

 

Dave,

It's Stevep from PY!!

There transmissions were slimmer than the Dual Coupling Hydramatics and the trans tunnels in the floor pan were narrower. Parts are available but are very costly.

 

My '64 Ventura was my second car. Bought it on a whim when I saw it sitting with a 'For Sale' sign. I was 18 and owned 2 cars - until I got the F-85 sold. Don't remember the Ventura shifting the same as the F-85. Seemed to shift more like a 'normal' automatic, like my dad's '69 Galaxie at the time.

 

Oh, then maybe the Pontiac guys just inherited the name "Slim Jim" The thing weighed like 120lbs!!!!

 

Thanks for the pics 1967 Tempest! Krash, does that look like the tranny you had in your Olds?