Won’t upshift at 25 mph

[Plrx]

When I drive at 25 fo 30 mph transmission stays in lower gear and won’t upshift even 

When accelerator is let off. 

[Moend]

Is it reving high. I am wondering if you are having issue or is it a general observation.

[Plrx]

General observation. I have never had an automobile that would not upshift when at the upper rage of rpms for the gear when the accelerator is let off. It is like I have a standard and leave it in 3rd gear and it slows you down. 

[Moend]

Hmm, did you have tow haul mode on. Also were you going downhill. Transmission now a days have multiple maps for shifting and it get affected by lots of variables. 

[oldmann]

Time for a dealer visit. 

[BlancoSilverado]

I believe you are observing a fuel savings program of these trucks. When going down the road (20-40mph) it will not go to an idle because its locking the TC and then it doesn't need to add fuel to keep the motor running,its using the engine to slow the truck down and keep it spinning. Like you said "It is like I have a standard and leave it in 3rd gear and it slows you down." it locks the TC (not pushing in the clutch) and it will slow you down. My truck does this also.

 

If you look at the instant MPG is it going to 99MPG? if so then what you are feeling is probably normal. BUT in doubt take it to the dealer.

[Wiggums]

Mine won't shift to the higher gears if I'm going downhill. Never on a flat surface.

[Plrx]

General observation. I have never had an automobile that would not upshift when at the upper rage of rpms for the gear when the accelerator is let off. It is like I have a standard and leave it in 3rd gear and it slows you down. 

 

 

I will will check the instant mileage reading and I will call the dealer. Thanks