[cletusvandamme]

My th400 leaks in 2 spots- the gasket leaks in teh front and I also get a puddle in the back. I checked both seals and they seem to be dry so Im thinking the gasket is leaking in the front and the speedo cable is leakin in the rear. Anyway I just keep putting in transmission fluid- will having over filled hurt it, and it seem to shift softer but still very quickly into 3rd. Could the excess trans fluid cause it to shift softer? thanks

2nd question: I want to build up a 77 impala that has a 3 speed- dont know if its a th350 or 400, probably a 350. I want to run a power glide in it because of one reason:TCI PRO-X 1.65 Straight-Cut Planetary Set For Powerglide Transmission. I want the whinding sound when I drive it, and I'm guessing these Straight-Cut Planetary gears will make that sound. My question is a power glide a good street trans?

[ericnova72]

Yes, excess fluid level causes the fluid to be thrashed by the rotating assembly, which can cause aerating(foaming) and overheating or the fluid leading to slippage and burnt clutches. A pint over won't hurt anything, a quart or more over is a potential problem.

[ericnova72]

You are picking a Powerglide for the wrong reason, and have you priced the straight cut planetary?? Pretty salty just so you can hear a whine in low, pretty goofy reason for deciding on a transmission. The lower than stock ratio gear set in a Powerglide will result in even slower acceleration than a stock powerglide, and even slower yet acceleration than a 3 speed automatic in a street car. Your Impala will be a real dog with a Glide. The fancy Powerglide gear set is intended for 800+hp 2400 lb or less all-out drag race cars that need it for strength or to calm down a car the over-wheelstands at launch..

If you gotta have a "whine" from you transmission, there are straight cut planetary Turbo 400's that came in heavy duty 1 ton and larger GM trucks, motorhomes and delivery vans. Stll a pretty goofy reason to pic a trans, the straight cut gear is there only for strength.

If you really want the trans to "whine", get a Jerico 4-speed manual trans, or just put a goofy gear drive timing set in the motor .

[cletusvandamme]

i like the whine in my monte ss, and would never run a gear drive, they are too annoying-id spend the money for a blower. The trans whine is much subtile and different. Ive also always wanted to try a powerglide, something different from my usual 400. I also looked for th475 gears and cant find any.

[ericnova72]

Originally Posted by cletusvandamme

i like the whine in my monte ss, and would never run a gear drive, they are too annoying-id spend the money for a blower. The trans whine is much subtile and different. Ive also always wanted to try a powerglide, something different from my usual 400. I also looked for th475 gears and cant find any.

You won't find the TH475 gearset unless from a used trans or a rebuild parts supplier, it's not common to even need them unless the GVR is 10,000 lbs or more.

[SSedan64]

Just have someone screw up your rear gear setup. You'll get a wine.