I have a 2000 f150 4x4 supercab with the 7700 payload package and the 4r100 transmission with the factory tech valve body. I have given this truck to my stepson and the truck now has 113000 miles. The truck will not up shift past 2nd and shifts harder from 1st to 2nd. The last fluid change was at 100000 miles. The fluid level is fine but there seems to be mud on the end of the dip stick. Should I get a local transmission shop to rebuild this one or purchase a remanufactured Jasper one? Any suggestions on a good transmission shop in the Kingsport TN or Big Stone Gap VA area? PS. stepson seems to like to go mudding and power braking.

 

The Jasper unit will likely have all the most recent upgrades built into the latest 4R100s, and you'll get a 3/36 warranty. That's what I'd roll with.

 

I would check to see if you have an electronic problem. Solenoid or something.

 

If a good tech rebuilds yours, it will also have all the latest upgrades.