So my old car is being weird and I don't know if I want the car anymore (unless something is solved). Its a automatic 1996 Acura Integra LS and yes the transmission is grinding in 4th gear.

What happens is when I am driving (in 4th gear) and if I go over 40mph and let go of the gas, the RPM drops down really quick and you hear a grinding noise until you step on the gas again. I tried doing it with the front jacked/lifted up but you cant hear the noise so what the hack? It has to be something...

The car has about 120,000 miles on it. I just changed both the front bearings and the front/rear brake pads so whats going on? Could it be my axel?

Oh and the other thing that I notice was when I had the car jack/lifted up and going around 40-70mph, when I stop or slow it down, the wheel on the driver side doesnt catch up with the passenger and when it does it jerks a bit then catches up with the passenger side.

IDK what do you guys think? Thanks in advance

EDIT* oh and the other thing is, it could be the timing belt? The belt hasnt been changed since 1996! lol idk??