Here's a question for the knowledgeable denizens of the hamb regarding Powerglide transmission cases. Here's the Powerglide that I just acquired. Look closely at the picture and you can see the two bosses typically used to run external cooler lines. You also have a great view of 2 of the big air cooling holes cast into the case. It has the standard Chevy bellhousing bolt pattern, so not a Vega transmission. Now here's the question for someone who really has infinite knowledge of the vagaries of GM oddball combinations. Those bosses are drilled and tapped for coolant lines. Further, it appears that they go forward to the pump. And finally, it looks like there was atf in the holes. Which leads up to my quandary. Was there some versions of Powerglides built from the factory with both the air cooling feature and external cooling? Some form of heavy duty, light duty Powerglide? Could something like a 250 six powered Chevelle have had a towing package that added on an external cooler? Or was this something possibly done during a rebuild to increase the durability of the transmission? As usual, thanks for the information, and let the verbal jousting begin!
I have seen holes like that in a Powerglide with hydraulic hoses coming out of them to some kind of control for racing. Don't know if that's what you have though.
Possibly a GM TorqueDrive semi-automatic transmission. Offered in '68 and for a few years after for 6 cyl. Camaros and 4 and 6 cyl. Novas. Didn't use a vacuum modulator or a conventional automatic valve body. https://www.chevyhardcore.com/news/the-torque-drive-transmission-chevys-manually-shifted-automatic/
A lot of '60s 6 cylinder powered Chevelles and Chevy IIs had these; no cooler in the radiator, and large holes in the housing for airflow over the converter. I put one in a V8 Chevelle, removed the plugs, and hooked up the cooler lines.
By the way, 6 cylinder transmissions had a 1.82:1 low gear and V8s had a 1.76:1 low gear. Why they bothered with a 3 percent difference, I can't say.
Owned a low mileage 63 Biscayne. Had the honey powerglide in it. Had to junk the trans couldn’t give it away
It's got the vacuum modulator. Haven't dropped the pan yet to look at the valve body, and also to see how much muck is in it. Another oddity might be that it does have the throttle linkage kickdown lever. So I'm still dazed and confused... I found a reference book on the internet archive site, but don't remember my sign in, so hopefully I wrote it down in my old school notebook!
You were told incorrectly.......62/63 were indeed offered with a 4 banger, but generally with a 6 cyl. The PG was in fact the air cooled case up to 64,then dropped in the Chevy II line for the newer addition with a cooler in the radiator. I have an early production 64/283/PG car, and it does have an air cooled glide in it, as well as 63 electronics (switches), etc...... GM was using remaining stock.
So did it also have the cooling holes? I've still got to find the numbers on this lump... maybe that will help identify the thing.
Some aircooled PG's came with the plugged fitting holes, the air cooled versions were usually in smaller, lighter, or lesser powered vehicles and the fluid cooled versions were behind larger engines and/or in larger vehicles, but I don't remember the specific breakdowns on that, so don't quote me on it. These PG's can easily be converted to use an external cooler by swapping out the front pump with one from an externally cooled PG, or by adding a cooler bypass valve in the air cooled pump.
Mine has the plugs, just like yours. But as Texas has mentioned, there is something in the pump, or the actual pump itself, that redirects fluid eliminating the pressure out of the case at the plugs. If indeed coming from a nova, and possibly others (GM), it will have a specific bracket/linkage for the "passing gear" .Through rods via bracket bolted to the back of the trans case. One rod to carb, one to linkage....
The more I search for information on Powerglides, the more rabbit holes I go down! I've never heard of the Torque drive transmission before, and I have to wonder what GM bean counters were thinking. So okay it was a bit cheaper to manufacture, but the development costs surely were never recouped. However I wonder if the aftermarket transmission guys got a hold of them and that's how full manual automatic transmissions came about for drag race applications. My warped mind then went off on a tangent, thinking about that and lock up torque converters. And could one be adapted to a Powerglide. Could be a good auto-X transmission... Well, back to the rabbit holes
I had that exact PG transmission in my 36 Willys sedan. The engine and trans came out of a 68 Nova it had a 153 Cu. In. 4 cyl. It was great I put a lot of miles on the car and sold it and the next owners put more miles on it. Pat
If I were home, I'd do some research... But I'm on a lonely stretch of Nevada highway, the kid is driving. Don't get too worked up about it, it's just an air coooled powerglide. Light duty applications. There could be some numbers stamped on it in a few places. There are also casting dates codes. And the tail length and spline count changed in the mid 60s. Have fun
Well I imagine the standard PG was well on the way to paying off most of its development costs. I don't imagine that very much money was spent to downgrade it to the even simpler semi-automatic TorqueDrive. If Chevy was guilty of anything it was probably their over-estimation of the demand for a manually shifted trans with a torque converter instead of a clutch. Maybe it was somewhat more popular for some fleet buyers like the post office. I've only ever seen two TorqueDrive equipped vehicles in the wild. One was a well-worn '68 or '69 Nova with a 153 c.i. 4 cylinder. The other was in a co-worker's fairly new at the time '71 Vega.
If I saw one, it didn't register on my teenage brain back then. No one was using automatic transmissions in dirt cars when I got into them, circa 1969. Now I look back to that era and think about what an injected small block with a Powerglide could have done. Oh well, back to the rabbit holes...
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