Up-shifting when decelerating?

[mp223]

Hi All,

5r55e
4.10 rear end
stock tires (255/70r16)

Driving around town at ~35mph in 4th gear (1.9-2k RPM) if I let off the gas I notice the tranny up-shifts into 5th gear and the RPMs go real low (like 1-1.1k RPM). When I press the accelerator it shifts right back into 4th gear and the torque converter locks and everything is normal (1.9-2k RPM).

That doesn't seem right to me, the truck has no business being in 5th gear at ~35mph and it seems like this would put excessive wear on the tranny.

Is this normal?

 

[PopRichie77]

I don't think it is going into 5th gear, when you leave off the gas the torque converter unlocks and the trans coasts, there is no engine braking in Drive position. When coasting the engine RPM will drop till you again step on the gas, this is normal.