Ok so I have an '81 Camaro with a brand new 383 in it and my TH350 seems to be going out. So here's the deal, this transmission has been rebuilt with a shift kit and it was behind a pretty weak 350. Then i got this 383, that is pushing 450 from the crank, and a month or two later my tranny started having trouble shifting into 3rd....It's fine from 1st to 2nd, but has soon as it gets to the RPM to where it should shift into 3rd it won't. It's like going between 2nd and Neutral and then after awhile it will go into 3rd, but when it is trying to get out of 2nd there is very little power going to the wheels. Plus when it is doing these shenanigans it will rev up on it's own. It gets really annoying and I'm sure it's not good on my new engine.

Thanks,
Derek Young

 

Sounds kind of like the pump is bad. But I don't know crap about the inside of trannies.

 

maybe the cables goin to the tranny arent adjusted correctly? just a guess...

 

+1 on the cable going to the tranny, try a new transmission vacuum modulator...

 

Sounds more like crud in the valve body, which would restrict flow to put pressure on the clutches. Have you tried to manually shift it from gear to gear and see what happens? If it still slips and revs it's more than likely a bad valve body, or a faulty shift kit.(or shift kit install) Might also check the vacuum modulator to ensure it's OK. Does it kick down and shift OK when you hit the throttle to pass?

 

Where is the vaccum modulator located at?

 

Also, I have noticed that there are run marks on my valve covers that looks like oil hasbeen coming outta my breathers. Cold that just be my breather gaskets aren't tight enough?

 

The modulator is located on the right side of the tranny pan. There's a hard vacuum line mounted to it that goes to the intake manifold.
Most of the breathers breathe and leave residue on the valve covers, especially after an engine gets some miles. I doubt it's just gaskets, but new ones may help a little. You should probably elimnate the breathers and use a PCV valve to allow the engine to breathe. I don't have any breathers on my engine. Got tired of the mess they made and just plugged them. They were dropped from Chevy engines when the PCV valve was first introduced.

 

Positive Crankcase Ventilation if I'm not mistaken?

So I would put them were my breathers went in then what do I connect them too?

Also, thanks for your help.

 

You DO want at least one breather in one of your valve covers, so that the crankcase can breathe in and out. When separate breathers were dropped, vent tubes were hooked up to the air cleaner assemblies instead, but it was still a breather vent. Put a PCV valve in the other valve cover, and hook it up to the base of the carb (the big fitting). If you get oil coming out of the breather, then you probably don't have a baffle inside the valve cover, and oil is coming right up. If that's a problem, they make a nifty rubber grommet that has a sponge filter at the base of where the push in breather goes, to help prevent oil from easily spraying up into the breather. Without a breather, the PCV will create all sucking out and no breathing in. Then oil and air will try to find other ways to get in and out, in places you don't want it to.