# 2 Speed Transmission I.D.



## bnichols04 (Sep 4, 2007)

I took the tranny out of my 67 lemans out to have it rebuilt. When i dropped it off the guy immediately said it was a TH350 not a powerglide??!! Not sure if the tranny was the original one or not. Is this even possible to get these mixed up? It only has 2 gears not sure if a 350 had 2 or not.


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## 05GTO (Oct 6, 2004)

If I am not mistaken the 67 lemans should be a st-300 2 speed automatic and the TH-350 wasn't used until 68 or 69 and is a 3 speed.


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## Too Many Projects (Nov 15, 2008)

If you know for a fact from driving the car that it only has 2 speeds, I would grab it and run to another rebuilding shop that can tell what you have. They do look very similar in appearance but if the mechanic doesn't recognize it chances are he's never been in one either. The ST300 uses a rod to kick down into passing gear where the TH350 uses a cable. The ST300 has the vacuum modulator in the right front of the main case where the 350 is on the left rear.


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## bnichols04 (Sep 4, 2007)

the weird thing is that it does not have a kick down cable. it has a electrical plug in the side of it and it does use a vacuume modulator. i know for sure that is a 2 speed. this probably isn't the original transmission i am just trying to figure out what it is.


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## 05GTO (Oct 6, 2004)

Here are a couple pictures of the st-300 in my 66 GTO it also has an electric kickdown.



















Here is a picture of the passenger's side'










Here is a picture of the turbo 350 with a kickdown cable;










Here is a picture of an aftermarket chevy powerglide, in 69 and 70 the powerglide was optioned on some pontiac b-bodies.










My 66 stays on the car lift so if you need more pictures let me know,


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## bnichols04 (Sep 4, 2007)

ok so the 300 has a kickdown? mine does not have a kickdown on it and it shifts perfectly. is that the only 2 speed that was offered to fit a pontiac 326?


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## Rukee (Feb 8, 2007)

bnichols04 said:


> the weird thing is that it does not have a kick down cable. it has a electrical plug in the side of it and it does use a vacuume modulator. i know for sure that is a 2 speed. this probably isn't the original transmission i am just trying to figure out what it is.


If that electrical plug is a single spade on the drivers side just above the pan, sounds like a turbo 400, which is not the right tranny for your car, but an excellent replacment. Snap some pics of the tranny and post them up.


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## topless lemans (Oct 7, 2009)

I just joined the site and just picked up a 67 lemans convertable. What can be done with the 2 speed trannies? Rebuild it or put in a 3 speed.


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## bnichols04 (Sep 4, 2007)

a turbo 400 is a 3 speed right? it only has 2 gears


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## Rukee (Feb 8, 2007)

bnichols04 said:


> a turbo 400 is a 3 speed right? it only has 2 gears


Yes, maybe yours is got second gear burned out or something else might be wrong with it like the kickdown switch stuck 'on' and it's holding it in passing gear ALL the time. A turbo 400 is about the strongest 3 speed automatic you can get. Well worth a rebuild.


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## Rukee (Feb 8, 2007)

topless lemans said:


> I just joined the site and just picked up a 67 lemans convertable. What can be done with the 2 speed trannies? Rebuild it or put in a 3 speed.


Either or. Whatever you like. I'd opt for keeping it original.


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