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

with all them miles it sounds like your bleeding trans pressure off causing the delay of engagement of gear, similar to low fluid.

id suck a qt of fluid out the dip stick tube, then dump in a qt of some type of trans medix of your choice. if it clears up you know your due for a rebuild soon.


and what color is your trans fluid on the dip stick? dark red, to brown? does it smell burnt?

if your not sure what that should smell like, find a friends car and check their tranny fluid, if its pink to red, smell it, then go smell yours. when the fluid gets dark, its burned up. you can smell the difference pretty easy.

Scottydoggs said:

with all them miles it sounds like your bleeding trans pressure off causing the delay of engagement of gear, similar to low fluid.

id suck a qt of fluid out the dip stick tube, then dump in a qt of some type of trans medix of your choice. if it clears up you know your due for a rebuild soon.


and what color is your trans fluid on the dip stick? dark red, to brown? does it smell burnt?

if your not sure what that should smell like, find a friends car and check their tranny fluid, if its pink to red, smell it, then go smell yours. when the fluid gets dark, its burned up. you can smell the difference pretty easy.

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The fluid definitely isn't pink. I'll take a picture after work.

How would I go about sucking out a qt out of the dipstick tube? Some sort of pump I can buy at the local auto parts?

dubyagee01 said:

Sounds like a weak trans pump.

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I seem to remember having a car with this problem many many moons ago. I think you're right.

Malik112099 said:

The fluid definitely isn't pink. I'll take a picture after work.

How would I go about sucking out a qt out of the dipstick tube? Some sort of pump I can buy at the local auto parts?

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i use thin clear tubing, pul the stick out, push the tubing down the dip stick tube till it stops, drape the tubing over the fender to the ground, then suck on the tube. clear tube lets you see the fluid, so you dont have to taste it lol

once the fluid is in the tube and lower then the trans pan it will siphon out on its own. i always seem to have a old oil qt laying around, id put the tube right into the empty jug till its full, then finger over the tube end to stop the flow, then lift the tubing up so it drains back into the tranny. pretty clean job this way. have a rag handy for the tube as it comes out the dip stick tube, the bottom few inches will be wet with fluid.

See if it does it after sitting in neutral for a while too instead of park. I'm not sure if these GM transmissions do it like my dodge but there is a check valve in the line that keeps the converter from draining while in park or off. If the valve is bad it will take a bit for it to fill back up when in drive or neutral. I have to start my truck and let it idle in neutral for a bit before it will move.

You can pick up a mighty vac evacuator. Defiantly makes it easier rather than dropping the pan and making a mess. If you’re doing to do that, I suggest getting a pan with a drain plug on it.

I have a pml pan, holds a little more fluid and it’s finned to help cool fluid

Sounds like low line pressure. You’ve probably got a pump problem or maybe a pressure sensor? I’m just guessing.


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I'm thinking bad torque converter.....?

A Tech2 can see any internal codes and of course see all the pressures so you're not guessing and wondering.