4L80E

[Tomjohn]

I have a 2004 2500 HD with a 4L80E transmisson. The truck has 12,500 miles. It sits in the garage up to four weeks with out being drove. When I back out of the garage the transmisson will slip, the engine will rev to 3k rpms before the truck starts to move. After this the transmisson does fine. Should I have this checked before the warranty expires. If I drive the truck every week the transmisson does not slip.

[GM-Tech]

I'd get it checked, but honestly, they're probably going to find nothing. You'll drive it in and it will obviously work fine at that time or for a week or two after.

 

Maybe you can arrange with them to leave it there for a month during a time when you would let it sit that long at your house anyway. That'd be the best way because if they don't see the problem, they're not going to go digging into the tranny.

[Tomjohn]

Thanks for the quick reply. You must love your job. I am a senior Industrial engine tech ror a Caterpillar dealer. After answering questions from our junior techs and customer techs for the biggest part of the day I am ready for a break when I get home.

[GM-Tech]

I do love working out problems in cars. I don't always have the answers, but the challenge is rewarding.

[lagrange151]

My88' blazer with a 700r4 would do that after sitting a couple of days, I figured all the fluid was draining back to the pan cause if I let it run for a min. before I put it in gear it wouldn't slip.

[KB06YUKONXL]

My88' blazer with a 700r4 would do that after sitting a couple of days, I figured all the fluid was draining back to the pan cause if I let it run for a min. before I put it in gear it wouldn't slip.

 

<{POST_SNAPBACK}>

 

 

 

What he said.....my 99 Suburban would do the same thing......once warmed up after a long idle period no problem.

[tercanb]

i have a 99 Blazer and when I try to shift from park to reverse or park to drive, the whole engine shuts down with a loud clunk. What would cause the engine to shut down when going into gear?

[breecher_7]

I'd get it checked, but honestly, they're probably going to find nothing. You'll drive it in and it will obviously work fine at that time or for a week or two after.

 

Maybe you can arrange with them to leave it there for a month during a time when you would let it sit that long at your house anyway. That'd be the best way because if they don't see the problem, they're not going to go digging into the tranny.

 

 

Please dont take this as a personal attack. But most service techs that ive delt with in the past dont know there *hole from there elbow and belong changing oil. I dont know how many times ive been told "we cant duplicat the problem" Then i duplicate it right there infront of them and they look at me like im the dumb one. I have absolutly no faith in the GM service techs around here, ive gotten to the point where I call the factory rep right away to get things delt with the right way instead of trying to tell these idiots how to do there jobs.

 

Example:

 

Ticking sound coming from the top of the engine, not typical valvetrain sound at all.

 

There answer:

We took a look at it and everything is fine.

 

REALLY? How did you take a look at the valvetrain WITHOUT removing the valve covers? You got xray vision?

 

Do they think everyone that owns a vehicle is a moron?

 

Sorry for ranting on and on about this but when you posted.

 

"there probably going to find nothing"

 

It just got me fired up......

[ryank1]

The convertors in the 4L80E will drain back into the trans if let sit and will cause the condition that you speak of. I recently had to move about 20 brand new 2500 vans with this trans that had been sitting for several months and every one of them did the same thing that you are describing.