Slipping Transmission?

[otis24]

2011 GMC Sierra. 5.3 V8. 147k miles. If you accelerate moderately, truck runs fine. If you punch the accelerator only slightly, rpm’s shoot up, motor revs, and truck doesn’t want to go. Mechanic at work said the fluid looks dark and has a slightly burnt smell. Wondering if transmission is slipping? Take it in Monday for a fluid and filter change. Will add LubeGard. See what happens.

 

[clinebarger]

Does it slip in a specific gear?

Pull the pan & inspect for metallic debris. If none is found.....Install a pressure gauge to see if the unit has adequate pressure rise.

 

[PontiacHO]

Regardless of checking for debris in the pan and line pressure, the damage is done and can’t be reversed. Plan for an overhaul or reman.

 

[martinq]

2011 GMC Sierra. 5.3 V8. 147k miles. If you accelerate moderately, truck runs fine. If you punch the accelerator only slightly, rpm’s shoot up, motor revs, and truck doesn’t want to go. Mechanic at work said the fluid looks dark and has a slightly burnt smell. Wondering if transmission is slipping? Take it in Monday for a fluid and filter change. Will add LubeGard. See what happens.

This is very common with lack of maintenance. Do you know the transmission service history?

 

[otis24]

This is very common with lack of maintenance. Do you know the transmission service history?

No, I do not. It’s my son’s truck. He purchased it this summer. I’m hoping that the problem can be solved with a fluid and filter change.

 

[Nick1994]

I had that with my Genesis, was a bad fuel pump. I could ease into the gas pedal and accelerate fine but something full throttle would downshift and get the RPMs up high, but wouldn’t accelerate.