i have a 2004 f150 hertiage 4.2 with a auto transmission. i have no reverse or overdrive in the truck .i was backing up one day and there was a pop like sound and the motor strated to rev up and i was not going anywhere. after that i tryed drive it forward and it strate out fine but at 25 or 30 mph it jumps out over gear and the motor rev up but if i take th o/d off it shift fine. its just stays at high rpms. i have very low income. i dont have the money for a shop to fix it there away i can fix it without paying a lot .or can i fix it.plzs let m know

 

If you are mechanicly inclined. Buy a book for your particular transmission. There is normally a chart of what is engaged and disengaged for each gear. You should then be able to take it apart to fix it. To be honest transmissions are not that hard to build. Just have to clean the pieces really well. I used to use gas. You can normally use an old flywheel and 5 gallon bucket as a stand. Don't be afraid to go in it. I talked my buddy into doing the same thing on his BMW, he fixed it himself. Only reason I say take it apart is because you heard a pop. Sounds like maybe u lost a band, maybe a servo. The 25 or 30 MPH are probable higher than normal RPM? Probably loosing it trying to shift to second gear. Just my two cents. The book probably has some good troubleshooting steps as well.

 

i am mechanicly inclined i just dont know much about transmission .i know they made 2 diffrenet times of transmission for my truck where would i look to find out what kind it is ?

 

If your truck is 4.2 v6, it aughts only have one transmission to choose from. If you meant 4.6 v8, then it's a 4r70w. Look in your door jamb sticker, and see if you can find where it says drivetrain or tansmission...there should be a letter or number code, then come back here an tell us wut u find.

 

Sounds like direct clutches and maybe a servo or your low reverse band. The direct clutch is very common in 4r70. They make a transmission block off plate through OTC where you bolt it to where the valve body goes and you can perform an air test to see where your issues are. This will give you an idea of where to start.