83 GP Trans Help Please!!!

[B Evil]

So I traded my motorcycle for a 1983 Grand Prix that has been in storage since the early 90's. The car has a 3.8 V6 in it and runs pretty good for being in storage so long. Unfortunately, there might be some transmission problems. First of all, I'm not sure which transmission is in it. Any way to tell the difference between the 250c and 350c?

Second, the previous owner said it had an old cork gasket on the pan and lost about a quart of fluid every other month. So I put in plenty of fluid to drive her home and she shifted thru the gears just fine. However, when I was almost home, I could tell she was losing her fluid again because the shifts weren't as smooth.

So I went ahead and changed the fluid, filter, and gasket. Once I got her all put back together, I took her for a spin. I don't know what happend but now the transmission won't shift out of 1st gear.

What could have changed between the time I drove her home and the time I put her all back together? Is there anything inpaticular I should be looking for?

Thanks for any and all help in advance.
-Bradley

 

[Brick442]

Scroll down to section 3 to ID your transmission by its pan . . . hope this helps

http://www.crankshaftcoalition.com/wiki/General_Motors_transmissions

 

[84GP455]

Well you can check the vacuum line going to the transmission modulator if it has one to see if it's cracked or broken, if it is the car will not shift out of first gear.

 

[3rdgentug]

i agree probly the modulator itself or the vaccum line to it

 

[B Evil]

How likely is it this modulator would go out during a fluid/filter change though? I'll def check the hose, but I'm not quite sure how to test the modulator itself. Any tips?

My whole expierence with transmissions ends after fluid/filter changes so you'll have to excuse my ignorance. I also noticed a small drip from the speedometer cable and my speedometer doesn't work anyways so I was going to be looking to replace that cable anyways. How difficult is it change the seal/bushing inside there at the same time?

Thanks again,
Bradley

 

[79GP6.6L]

The speedo sender seal is just an 0-ring. Easy to change. Did you recheck the fluid level after you got it home? Was it low?

 

[3rdgentug]

they go out..it happens
i had 1 in my s10 blazer that had a v8 in it worked perfect for about a year
i put a higher stall in it, never even touched the modulator, put the transmission back in. wouldnt shift~!
long story short, 2 weeks later and another tq convertor that did the same thing we figured out the modulator had gone bad.