98Lariat4.6

the transmission in my 98 f150 4x4 just went out. having it rebuilt by a shop isn't in my budget so I will be doing it myself or having it done by someone I know. Either way I will be buying the parts myself. Who makes the best rebuild kit for the 4r70w? My engine has pi heads and aftermarket cams so it needs to hold a little extra power. any advice would be great.

Jbrew

Sounds like a nice truck, can't answer your question directly, - I've never fully rebuilt one, just went through the bottom end because It wasn't worth investing in the tools needed to go further. I like doing my own work, saving cash as well.

UNLESS you know someone (friends with) that rebuilds them, your pretty much at a shops mercy. Probably going to have to bite the bullet and get it done by a good shop. Just do your homework, - it pays big time.

Good Luck.

screamineagle

The only transmission I have been through was from my old Ram. If you plan on doing this yourself, make sure you have someone knowledgable readily available. Basic tools is all you need for a basic rebuild. I made my own slide hammers out of all thread and a piece of pipe for removing the front pump. The most important steps is to have a clean working area, don't reuse the old convertor, and at a minimum, flush the cooler. Replacing the cooler is the safest route. Good luck and keep us posted

Jbrew

Yea, you have to back flush the coolers...correctly! Or it could be all she wrote very fast. Still using my factory cooler, but it was questionable whether or not I got it all out. I got lucky I expect. New cooler is the way to go and Ford has an in-line filter kit you can add in as well.

The OP has substantial gain in torque and power with his set up, so he'll need to build it up a bit IMO. 230-235 rwhp I expect.

screamineagle

I agree it should be beefed up a bit. Just to be safe if nothing else. You can't "over build" an automatic IMO, the beefier the better