I finally have got the cummins in my motorhome running good and now the trans. will slip in 5th gear if I try to push it hard. I installed a transgo shift kit which replaced 2 valves behind the servos and don't see where that did any good. I think I need to raise the pressure but not sure how to do it. It's a MH2500 series trans. I know what I'm using this thing for is a little out of the normal for this trans. , on Allison's web site they rate the trans. for 33000 lbs . The motorhome and stacker trailer weighs 51000 lbs .