The shift schedules are adjusted for altitude. The shifts will happen at lower RPM for a given pedal position.
Mark, well said. My trailer brake controller was shorting out and causing this behavior with the torque converter lock up. I unplugged it and the transmission behaves like brand new.Often a lockup problem is electrical. A burned out brake light can cause this, either side OR the center brake light on the rear of the cab. Just replacing parts without any diagnosis gets very frustrating, not to mention expensive.
Great so there must be a problem with my rebuild. Maybe a backwards roller clutch?
I've never heard that, and have no idea what would cause it.Mark while we are on this clutch deal, I have a question. I have noticed after sitting for weeks these trucks make a sound when coasting at speeds under say 40 mph, that sounds like the coast clutch releasing and engaging back and forth. You can hear it by the way it effects the engine.
They seems to clear after driving for awhile and does not return till they sit for weeks. I noticed this on a fleet that gets rotated to and fro a separate location and lot.
If either roller clutch were backwards you'd have a lot worse symptoms than this. My guess is that there is a leak between the coast clutch and the overdrive clutch.Great so there must be a problem with my rebuild. Maybe a backwards roller clutch?