We just bought a used 2015 XC60 T6 FWD. when going up a moderate hill in cruise control at any speed, the cruise doesn't upshift for about 4-5 seconds. This Boggs the engine down until the vehicle shakes. I know bogging a forced induction engine is terrible for it. Any ideas for a fix? Or is this normal.

 

It's not heat related. It's that the transmission won't upshift when going up a hill. So it's in one of the final gears (7th or 8th) for about 4 seconds or so before it finally realizes that it needs to upshift