I have a 1994 lightning and the tranny shifts hard form 1st to 2nd, other gears are fine. I was thinking it might be a chip in the computer. I assume the coputer would have the chip stuck in the end of it like a later model mustang? What is the easiest way to pull the computer. Also the speedometer jumps around alot so this might also affect it so I will be pulling the rear end cover and looking at the speedo ring and checking for damage there. Any other ideas?
Thanks
Charles

 

First geuss would be the exciter ring. thet would cause the speedo to dance and also funny shifting.

 

I would check your TPS

 

I am going to tear into it first thing in the morning and let everybody know what I find.
Thanks

 

I had a similar problem with mine. It would shift hard every now and then then it would shift out of overdrive.
Now I wouldn't consider myself a mechanic but, I talked to a good transmission guy who told me it was probably was the speedometer. I replaced it last week and VIOLA!!! Problem solved.
Stupid Electronics...