OK...I searched the archives and still would like to here your fluid recommendations for my 4R70W 2003 F150 4x4 tranny fluid swap....I'll be doing it myself. I will be doing the entire fluid and filter change. I have 30K on the truck and tranny and Mercon V is the current fluid. The trans is working fine with no issues....

I'm interested in synthetic trans oils or anything that will give me maximum service life of my transmission. I dont mind paying a bit more if needed. I love my truck and plan to keep it as long as possible.

Thanks for the input.

Terry.....

 

As always I recommend motorcraft merconV fluid and service it every 25-30k. A big cooler is a must as well.
Alan

 

I think most of the time motorcraft mercon v is recommended, and using anything else can(and has) lead to problems. dirtyd0g is very knowledgeable, and I would use his advice. Cooler running tranny is always good.

Troyer performance has a chip or tuner that adjusts the transmission to run about 30 degrees cooler(I believe it changes some shift points and torque converter lock settings), however it might not make that much difference(temp difference) unless you are towing.