Transmission slip?

[Mbrooks420]

I saw a test someone did online with the lucas diff additive. As soon as the Lucas was put in the oil started foaming real bad, and turned white because of all the trapped air. Not what I would want in my gears.

 

[RickOTR]

I'm not sure about the 4R55E, but I do know on the 5R55E that you can adjust the forward and reverse bands. They are located on either side of the neutral safety switch. Just back out the jamb nut a few turns then turn the square adjusting nut in until it stops turning while holding the jamb nut with your wrench. Then back it out from 3/4 to 2 turns, then tighten the jamb nut. Seems 1 turn worked well for me. I no longer have a jump in rpm and the shifts are smooth.