Originally Posted by Andrew H
When I let off the gas to coast it feels like my truck has a retarder system that slows it down and drops to a lower gear right away. Does anyone else have this issue? I searched the Tranny flash TSB but I thought that was just to help it shift smoother into higher gears.
Oh yeah its an automatic 4.0 with no mods to engine.
Normal. The fuel injectors kick off while coasting at a sufficient speed. It feels like a downshift but if you look at your tach the RPMs shouldn't change immediately. If you continue to slow down while coasting then you will eventually downshift.
The TSB you're reading typically happens when accelerating at slow speed, often when rounding corners or something similar. You try to accelerate but the truck seemingly can't find the right gear so it lags a second or so before acceleration starts. I had this as well and that TSB cleaned up the behavior almost completely.