My tranny was built about a year ago with redline clutches ,ATF+4 fluid etc. I talked to a buddy of mine who works on trannys, since I will be using his lift, about changing my tranny fluid ,filter , governor selenoid & pressure switch next week. He told me not to use ATF+4 fluid because it causes slip and to use Mercon 3 / dextron instead which will firm up my shifts and cause less clutch slip. Im kind of weary about this because Ive heard of tranny problems arrising with using different tranny fluids. Will this Mercon 3 / Dextron be allright to use on my 48RE? Thanks

 

Talk to Redline, see what they recommend. Different clutch disc manufacturers recommend different types of fluid.