07 Denali won't move in fwd or rev until 1000rmp

[Malik112099]

i have a 2007 Yukon XL Denali with 24X,*** miles. I cleaned the MAF and throttle body and dumped some sea foam and octane booster in the tank. Next step the weekend was to change the plug wires and plugs since I don't know the last time they were changed.

No codes. Runs like a champ. No funny sounds. When I shift into reverse it won't move until I hit 1000rpm and then it feels like it ramps up smoothly to power. It does the same in drive. After driving around for a few minutes it goes away (takes off from stop signs just fine) until I sit in park for 2 or 3 minutes. It drives fine. Shifts fine. No odd noses when it "lurches" into drive or reverse at 1000rpm.

Checked tranny fluid and it's fine. No leaks. Not sure what this could be.

 

[kbuskill]

You checked the transmission fluid with it up to operating temperature, correct???

 

[Malik112099]

You checked the transmission fluid with it up to operating temperature, correct???

Correct

 

[Malik112099]

My buddy is doing some research and he thinks it is delayed engagement

 

[kbuskill]

I am also going to assume this was not an issue before doing the work you described?

 

[Malik112099]

I am also going to assume this was not an issue before doing the work you described?

It was not. It shifted a little funny from 1st to 2nd like it was delayed a little but there was no issue with it not moving until around 1000rpm

 

[sumo]

Binding brake caliper?

 

[Rocket Man]

Binding brake caliper?

Maybe check for this by shifting into neutral at about 20 mph and see if it slows quickly on it's own.

 

[swathdiver]

A bad torque converter can do this but do the simple stuff first, check the brakes and maybe change the transmission and transfer case fluid. Change the differentials too for good measure.

 

[dubyagee01]

Sounds like a weak trans pump.