Long story that I will attempt to keep to the important details.

I've been working on a body off restoration for the past year. Last summer around June, when I was about to put the body back on, I was digging into the tranny. I had put in a B&M shift kit and then on further reflection decided to get a rebuild done on the entire tranny. The shop at the time said that it was a good thing too. The car had been sitting for about 10 years and the clutch plates had separated. So, back in August when I put the motor and tranny together, the body back on, broke in the motor and did a few simple sprints up and down the street in my neighborhood. That's all I could do at the time since it was open headers and loud as heck! In retrospect I never got it through the gears to make sure the tranny was ok.

Since then I had her in the garage doing the paint, interior, and exhaust. I just finished the exhaust today and fired her up again. The motor purrs now with the new exhaust and I can finally hear when I run the car as well. Which is where the tranny issues now appear. I can put her in reverse and back up at speed with no bad sounds. But, when I put her in drive, wow, it's like someone opened the gates of heck and screaming banshees are let loose. I can sprint her up the street but again, no change in the sound and no shifting either. The fluid levels are good as well.

So, what do you think is the problem? I figured the tranny shop should have tested it but when I got it back last summer it was dry as a bone so that seems to be a bad assumption. Question is, is it from me screwing up the shift kit or a problem the tranny shop did in the rebuild. What should I do to try and sort it out?

 

not sure but can you hook up a pressure gauge to this like i did on the 700r4 for diagnostic purposes

 

Where would I hook up a pressure gauge? Sorry if that's a stupid question but I know squat about tranny's.

 

If you did the shift kit after the tranny shop rebuild it could be your fault, but if the tranny shop did the rebuild after the shift kit take it back to them for warranty.

 

i'll look when i get home on my th350 i took out of the 77.....onthe 700r4 its onthe drivers side and is a pipe plug

 

Is your vaccum line hooked up to the modulator? This will prevent it from shifting.

 

 

Yes, hooked up to manifold vaccuum. Remember, my first order problem is it's screaming like a banshee as soon as I put it into drive. I don't even have to be moving.

 

Sorry, I am not familiar with "screaming like a banshee".

 

I think he means he hears it going "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee e!" when he puts it in gear...

TH-350s have drive? Mine doesn't have a D... only 1,2,3,N,R,P...

 

That about sums it up on the sound. Come on guys, when I say drive of course I mean setting it to 3.

 

why wouldn't high pressure and fluid make that noise as it tried to pass through an opening that wasn't fully opened???

 

I don't know, would it? You know, as loud as it's screaming I gotta believe that I would have heard this even over open headers last summer. Any reason why sitting for 6 months could do this? I did replace the tranny pan last week with an aluminum pan to dress it up some and seal a gasket leak. The old and new pan were identical in depth to the best I could measure.

 

In that situation I'd take it to Aamco and let them do a free diagnostic.

 

He means it sounds like an old Pontiac show car.

 

I'd drop the pan again and look closely. The T-350 filter attaches with screws and picks up on the top side of it...but it sure sounds like it's getting air somewhere in the pickup part.

Screeming is a sign of air in the pickup side of pump. Don't run it too long..it's going to burn up eventually.

Weird that it doesn't do it in reverse....that worries me. So it makes noise as soon as you put it in a forward gear even if car isn't moving?


JIM

 

Yep, you got it. Strange to me too. I spoke to the tranny shop and he was equally as stumped. Even though it's technically out of waranty having been rebuilt last May on a 6 month warranty, he was really cool and said if it came down to something they would do it for parts. The problem is that he's 25 miles away and a $75 tow charge to get the car there. Maybe I'll just drop the pan again, put the old one back on for grins. It's a royal pain but not impossible.