I bought this car 2 months ago and have been transitioning it into my daily driver. It's a 1997 LT1 car with about 110k miles.
I've noticed after driving it more that the transmission has issues. The first is that at highway speeds it will temporarily lose overdrive when throttle is decreased or let off completely. For example, when cresting a hill the revs will jump 500-700rpm for about 3 seconds and then it will "catch" and everything will be normal again. If I give it gas while it is doing this, the revs will continue to rise and I feel some moderate vibration but no acceleration until it catches again.
The second issue presents itself during hard acceleration. If it's "floored" from a stop, the car will lose wind at 4000rpm and take a very long time to reach redline where it then shifts hard and spins the tires. During that hesitation the whole car will vibrate. It will also exhibit this behavior at higher speed on the 2-3 upshift. I have not driven it fast enough to see redline in 3rd.
A week ago the SES light came on and the Autozone code reader indicated "all three" shift solenoid codes were tripped. It was reset and has not come on again but the problems persist. I should also mention the fluid looks red still but the dipstick constantly gets pushed out of the tube, I suppose from excess pressure within the case.
Can anyone here help diagnose these issues?