High rpms, slow accel, hard shifts, no power

[ShadowRejects]

Drove fine to class and I came out and my truck started up fine but it immediately started shifting hard and when I full throttle it, I go no where. Its really worrying me because the trans was replaced less than 20,000 miles ago and has been driving fine til today.

Any ideas? Fuel filter? Pump? Trans? I'm praying it's not the trans .

 

[SCOTTYINWV]

I would think it would be in the torque converter department. But I'm no auto guy

 

[dowsewashere]

Torque converter or shift solenoids. The issue with the fuel system is that the truck would sputter. You never mentioned that and since the engine will rev up to whatever high is, then the engine does not sound like the issue. More the 35in tall tires and 3.42 gears have taken their toll.

 

[ShadowRejects]

I drove it home and noticed it doesn't shift. It stays in one gear, plus I also noticed my exhaust is very rich. Almost like it's clogged. Which makes me wonder how a shift issue effects exhaust..... I'm so lost right now.

 

[92GMC]

have you tried to manually shift it?

 

[ShadowRejects]

have you tried to manually shift it?

I manually shift in first and it takes off a little quicker but the exhaust is still acting clogged and the truck seems to be running rich/at high rpms and the service engine soon light is on,

 

[ShadowRejects]

Update: After watching multiple videos, i almost want to say my cat is clogged. It has all the symptoms, what is funny is my cat is new... Strange. it has maybe 2500 miles on it.

 

[92GMC]

Your cat convertor has nothing to do with your trans shifting.

 

[volunteerff21]

That sounds exactly like what happened to me when the wiring for my 02 sensors came in contact with my exhaust manifold and melted.

 

[SCOTTYINWV]

Unbolt your y pipe and see how it drives with open manifolds. I don't see it even hitting high rpms with a clogged cat, but stranger things have happened...