I just recently bought a 99 F150 5.4 4x4. The transmission just started to slip so im preparing to replace it. I was considering going in with a standard transmission and was hoping yall could give me some advice on what problems i might run into. And which transmission do yall sugest i go back in with? Thanks for all the help.

 

Well, the big issue that you'll really have to address is that the computer is expecting an automatic transmission to be there. It'll not at all be happy and really cause you trouble.

2 routes to fix this are to get a custom tune to set the transmission type in your computer to manual, or to get a computer from a factory manual equipped truck with identical equipment and have PATS reset for your truck.

D

 

There was never a manual available with the 5.4 in a F-150. The 5 speed M5OD-R2 was a light duty Mazda transmission and was only used with the V-6 and 4.6. It will not hold up behind a 5.4. There was a heavy duty ZF behind the 5.4 in the Super Duty, but it requires a body lift or a big hole poked in the tunnel to put it into a F-150. NOT a feasible swap with a 4x4, there are transfer case and driveshaft issues.

I would get your automatic rebuilt.