No 3rd or 4th gear in auto tranny 1986 300e

[valu8or]

My son has an 86 300e and the transmission will not shift gears. He says he hit a pot hole and now the problems started (I dont think it happened that fast).

As I test drove the car the tranny would only stay in low gear. Not sure if it was 1st or 2nd, but the tach was revving at about 5k doing 20 mph. I disconnected the kickdown switch behind the gas pedal and could get it to start in what appears to be 2nd and stay there. It would not upshift at 5k even.

Today we put some trans x in and now it will start in 2nd and not upshift from there. If I put the gear selector in 2 it appears to go to 1st gear when going slow and when I put gearshift to 3 it appears to go into 2nd gear also. It appears to me that the trans x has at least helped it this much.

It does not appear to be the selector being wrong as reverse is reverse and neutral is neutral and drive makes it go forward.

Before he has to cough up all the dough he has for a rebuilt tranny is there any other things I can check to make sure the tranny is bad? I have checked the fluid many times and it does not appear to be burned and the level is good.

Thanks for any and all information you guys may have.