I have a 2001 XLT 7700 Series, F150 Supercab you know the one with seven lug wheels. I'm going to get my tranny flushed and changed. I know that it takes Mercon V fluid so should I add some Lucas additive or should I just use the friction modifier? And another thing how often should I change my rear diff, fluid? What type of fluid should go in it or anything that I should do to enhance the life of it and the performance?

 

Use straight Mercon V fluid only. And don't take Mercon and add crap to it that claims to make it a Mercon V fluid. Plenty of other guys here will say the same thing.

 

Thanks I appreciate the advice, and Ford as bad as I hate to say it they need to make a better tranny, or get in with someone like Jasper/Allision

 

Ya they did it was the C-6