Just rebuilt a c4 and have a couple problems

Hey guys I just rebuilt my c4 and got it in the car earlier today and the good news is I have three forward gears and reverse which to be honest thats more than I expected. The problem is it kind of slips into 2nd gear it does not slip once it engages it just takes it a second or so and it also flares up between 2nd and 3rd. When I`m in 3rd I can kick down to 2nd under power and it works perfectly , same for first its just the up shifting that is giving me problems.

Any and all advice would be greatly appreciated !

 

Did you install a new vacuum modulator? Also did you do any valve body mods? Mine did something similar after a shift kit install that I apparently did wrong or was just a crappy shift kit.

 

I did not install a new modulator not because I`m too cheap to buy one I just didn`t think about it untill I already had it in. I will test it in the morning. I put a transgo shift kit in it from what I understand its about the best one out there. I also installed a PA servo.

 

Did the shift kit ask you to drill any holes in the separate plate to a larger size? I did that with a b&m shift improver kit an I got the flare up on upshifts. Long story short after trying all kinds of things (like a new modulator) I put the stock separator plate back in but with the rest of the shift kit mods. Problem was solved and it still barked the tires on both shifts. I had an "H" servo in mine. My advice to people now is to not drill the holes out.

EDIT- I am far from an auto trans expert, this was just my experience.

 

That was the same crappy kit I used. A P.A Valve body fixed mine.

 

I dont think the kit was crappy. The directions for "stage 2" or whatever they called it(firmer shifts) required drilling a hole or two to a larger size (they supplied the drill bit). I think if I hadnt drilled the holes it would have been fine. With the stock plate back in the shifts were awesome and the trans was completely trouble free for years. When I sold the vehicle my only regret was letting that trans go!

 

If the directions say to drill holes and it doesn't work like it's supposed to, that's my definition of a crappy kit!

 

I see you're point Dan.

Super Maverick, you will probably have better luck starting a new thread with your question. More people will see it and respond versus your question being buried in the middle of a transmission discussion. Good luck!

 

Thanks !

Yea I know its part of it I am hanging my head in shame .

I put 25 in lbs of vacume on it and it leaked down pretty quick so I will put a new one on when I get home friday but I have never heard of a modulator causing shift flares .

 

Yup I`m an idiot new modulater fixed the problem. Now that that is fixed and I got to drive it a little bit I have noticed some other things I`m not happy with. I am not impressed with the second gear shift , it doesn` seem any better than it was before I installed the shift kit. I gess I`ll pull the vb back out (oh how I love tranny fluid running down my arm and into my arm pits) and put the "race only" spring in and see what it does. Something that realy bugs me is it will not hold the gear I put it in and it won`t downshift on demand .