2017 with issues downshifting from overdrive..

I have a 2017 crewmax 4x4. Bought the truck used with 79,000 miles. I now have 86,000 and the truck will not hardly downshift from overdrive. When cruising, if you get to a hill or something and need more power, it will begin jerking, and cutting out, like it wants to drop a gear but can’t, and it won’t stop until you almost floor it and make it downshift or until you let out of the gas and make it stay in OD. Literally started overnight and has gotten progressively worse. Closest Toyota dealer is well over an hour away..would rather take it some place else but it’s not throwing any codes so not sure they could tell me what’s up. Anybody else had this issue?

 

I’m no expert, the only thing that comes to mind would be maybe you’re low on transmission fluid. How does the transmission shift other than downshifting from OD?

 

Have you tried a manual downshift to 5th or 4th while it’s doing this?

This sounds more like an engine / fuel / ignition issue to me. Any lights on?

 

No issues other than downshifting from overdrive

 

I have tried to manual shift, doesn’t do it when I shift it manually. Don’t have any lights on, my first thoughts were same as yours, I changed the plugs since that was a cheap easy thing to try, didn’t help.

 

Valve body or solenoid might be gunked up if transmission not serviced regularly.

Try a full throttle run from a dead stop. If there is normal power and no symptoms then the engine isn't the issue. Its in the shifting or transmission.

Does it do it reliably or only when cold?