Hey all, after searching 15 pages to see where I might put this, I gave up. I am new to forums, and not really sure how to do it.

Anyway, I have a 2000 Chevy Silverado LS, auto, 4x4, 3 door, with a 6.0 Vortec that between 40mph and 50mph will hesitate unless I take it out of "D" and put it in "3"... basically raise the RPM. It doesn't matter if I am going up a slow grade, steep grade or flat.

If I try to keep it at, say 45mph, it will miss/hesitate. Took it to a mechanic and nothing pops up on scanner even while the rig is doing it...

So what can I do to stop it from doing that? It is getting worse, the more I drive it, but it's our only vehicle.

I have tried fuel injector cleaner, gas treatment, and running the premium (which helps lessen the regularity of the hesitation, but doesn't prevent it).

Thanks in advance for any info!

 

So what was the problem? Did you ever get it fixed.

 

No one has replied yet except you, so no I still have no idea.

Dad-in-law said it is probably the tranny since it is at basically the same speeds, and taking it out of the RPM range it is in, makes the problem disappear... gonna try changing the tranny fluid/filter again. Last one was 8 months ago, who knows.... Do you?