I have a 91 RS v6 auto.
Been noticing when I accelerate sometimes there's bump or knock underneath right about were the shifter is. Doesn't always happen but noticeable when it doe's.
Also after I've been driving a while and everything is nice and warm the oil gauge fluxes. Doesn't seem to leak oil - that I've seen.
It's also been recommended that I flush my trans fluid. I have no clue if it's ever been changed but it doe's have a good color and doesn't smelled burnt.

 

Check your transmission cross member bolts for tightness and your transmission mount on your first problem of the knock.

 

The gauges on our cars are notoriously inaccurate. You can hook up a mechanical oil pressure gauge to check it out. I know it wont hurt anything to change your transmission filter and fluid, at least you will know when it was done.

 

I had a knock and it was a torn tranny mount a 7$ part at autozone

 

i had that happen on my 92z28, i would accelerate and it sounded like something wanted to pop up thru my shifter, it was the tranny mount. The rubber was slit down the middle. Easy fix I believe its 5 bolts and the mount is off, put the new one on and the bolts back in and youll be good to go.

 

Cool thanks, I'll check the trans mount and see if thats the prob