Hi, I've been bringing a 2001 3500 maxi back to life with 1 major problem remaining. Transmission flush and filter did not fix the following although van is driveable.
On acceleration the tranny is "waiting" too late (too high rpms) to shift. On fast aggressive accelerations shifting is "too high" but smooth thru entire range. In slower traffic shifting is again "too high" but pops fairly roughly into first couple gears. More severe is when traffic forces you to accelerate at a slow rate then maintain a slow constant speed but at a higher rpm than that gear should be in and then you are forced by traffic to slow down which slowing then causes the upshift (not downshift) that should already have taken place- and it is a rough banging shift for sure.
Any ideas would be greatly appreciated.