I am just finishing putting a Cummins in a Suburban. It is an early 12 valve motor. For the transmission I used a 48RE out of an 01 with 30k miles. I changed the tail shaft and vlve body on the transmission to convert it to an RH. Anwyway, shifting seems to lag a bit. For example with my 4:10 gears I am going into third at around 35 MPH. My pump stops fueling at 2600 RPms and slows down at 2400. It seems that about the time my transmission wants to shift, I am runing into my pump defueling. I am curious where your transmission is shifting on your 98. 5 to 002 trucks, and where does the VP44 defuel stock? I am thinking my shifts would be better if I increased my defueling speed. Any thoughts?