Ok I drive a car that has 238000 miles it's had some problems not too bad but the last few days its getting worse. I think it may be the transmission but here is what's happening, the damn thing drops into reverse and whines when I put it in drive.

Then I will be going down the road when I go to stop the wheels shake and there is a grinding noise on the front underbody shakes horribly

Then it slips in and out of gear I'm afraid to say I think its on the way out feels like it may stall when I go to accelerate from a dead stop and rpm goes wild some days it goes fine like normal but on other days the dial on the rpm will not go above 2200 rpm I need to know if I should just give it up and get another car by the way its a salvage title so it was given to me for a grad gift two years ago so there it is I really need an answer

 

The trans goes into reverse when it should be in drive?

The grinding and shaking may be the brakes.

What condition is the transmission fluid?