I have a montana with the lippert pump as well. I took my pump out cleaned it all up with brake clean as well and let dry. Only difference i did was used the permetex product made for ATF fluid. I gooped the******out of the oring a assembled. It been about 3 weeks and all is good. I also left my slides out figured this way there would be less fluid to deal with and less air intrusion. I am sure using the black will work fine. That is what i was going to use. Then i saw the stuff for ATF. I did let the pump sit for the full 24 hrs for the curing. Furch5263