Ok so I have spent some time on the message boards reading up and trying to figure out how to fix my problem. I just bought an 87' IROC with a rebuilt 350 and the stock transmission modified with a shift kit. I love the car but hate the shift kit. I definitely would like it out. I am also thinking it may play a generous part in my problem. I can honestly say I'm not the most technically savoy when it comes to cars. It worked fine for three weeks and then today it stopped shifting from 2nd to 3rd. The RPM's rev up as if it was in neutral and absolutely nothing will get it into 3rd or 4th. It shifts just fine from 1st to 2nd but that's it. Any solutions and or ideas would be highly appreciated.

 

Well, the problem is that it worked and now it doesn't. I don't know that you can blame the shift kit for that. I need some more specifics though. It won't shift 2-3 at WOT, or it won't shift 2-3 at all?

 

I can only speak from my personal experience and this sounds like the classic 3/4 clutch pack failure that plagues the 700R4.
I've had a couple of these transmissions (there are three on my work bench) where all seems well, with shifting as you expect it and then there's no 3rd (or 4th) the next time.
Unfortunately there's little that can be done except for a teardown and rebuild.
The properly specified shift kit or reprogramming kit will be designed to help minimize this problem however it won't repair it once the damage is done.
You can verify if the clutch is toast by dropping the pan. It will undoubtedly be full of friction material.
There are other causes of no 3/4 gear ( governor, stuck valves in the valve body, etc) although in my case it's always been the clutch.

 

I sure do appreciate the responses. I have prepaired myself for someone to do a rebuild for me. the car has 117,000 on it and I am positive that the guy I bought it from beat on it quite hard. I am guessing since I can't do it myself that when the tranny is out that I should have it brought up to par so I am not dealing with other tranny issues come this summer ? I don't blame the shift kit but as far as personal preference goes I surly can do without it.

 

It won't shift into 3rd at all. Today I noticed a faint burnt smell to the fluid on the stick.

 

A shift kit, properly designed and installed, will actually help with transmission longevity. It dosen't need to be harsh or uncomfortable to drive.