Not totally sold that the trans is shot.

[5strmtrp]

I went and changed out the fluid 3 times last week. Borrowed a manual transfer pump from a friend of mine. Pumped out the fluid thru the dipstick tube.

Each time I did it the fluid got cleaner. It’s how the color it’s supposed to be. Going to drive it a week and keep checking the condition of the fluid. If it stays normal I’ll drop the pan again and replace the new filter with another one for added insurance.

If not then I have an appointment at the end of the month at my local shop to replace the trans with a GM rebuilt one.

 

[5strmtrp]

I went and changed out the fluid 3 times last week. Borrowed a manual transfer pump from a friend of mine. Pumped out the fluid thru the dipstick tube.

Each time I did it the fluid got cleaner. It’s how the color it’s supposed to be. Going to drive it a week and keep checking the condition of the fluid. If it stays normal I’ll drop the pan again and replace the new filter with another one for added insurance.

If not then I have an appointment at the end of the month at my local shop to replace the trans with a GM rebuilt one.

After nearly 500 miles of driving, the fluid looks normal and it’s shifting perfectly fine. Hopefully I dodged a bullet here, will keep monitoring the color of the fluid in the coming weeks and go from there.
Appreciate all the help you all have posted.

 

[Doubeleive]

some other things to consider if the issue returns or if you just want to do some preventative maintenance, some previously mentioned but MAF could be a culprit (about $70), clean the throttle body, run a couple bottles of injector cleaner thru it for the next few tanks fulls, new air filter, plugs-n-wires were due at 100k, all 4 02 sensors are due at 100k also.
beyond that you could have a injector service done, some places have a machine or tool that connects directly to the fuel rail and they run it thru that way, generally runs about $80 for that service.

 

[5strmtrp]

some other things to consider if the issue returns or if you just want to do some preventative maintenance, some previously mentioned but MAF could be a culprit (about $70), clean the throttle body, run a couple bottles of injector cleaner thru it for the next few tanks fulls, new air filter, plugs-n-wires were due at 100k, all 4 02 sensors are due at 100k also.
beyond that you could have a injector service done, some places have a machine or tool that connects directly to the fuel rail and they run it thru that way, generally runs about $80 for that service.

I went thru my receipts and things I’ve done to the truck. All of this was done in the past 20k or so miles. Last year I had the intake cleaned by the mechanic I use. He mentioned that these trucks are known for them getting gummed up. I will clean the throttle body again, and the plugs wires were all done around this time as well. The weird thing is these truck only have an in tank fuel filter. My 03 Silverado had 2 in tank and along the frame near the middle of the truck. That was originally my 1st idea where to check and replace.

 

[avalonandl]

There is an updated accelerator pedal assembly avail from GM...
Your Throttle Body could be gummed up...
If you drive it manual LOW and put it in "4" , Im told that the AFM will not kick on.

As far as the VVT, it runs off oil pressure and gives the camshaft advance/retard
You should be able to see if its being commanded with a good scan tool.
And you can compare your TPS values to Peal Position values to see if that's off too

AFM can kick on anytime that certain parameters are met.

 

[Swaggerwagon]

Can’t tell you with 100% certainty what the issue is, it I can tell you it’s NOT the gas pedal. Any pedal issue, even for a millisecond, will make the engine drop to idle speed, until you shut the truck off. And you get an immediate ‘check engine’ light. Since we’re spitballing here, it’s been my experience that a clogged fuel filter will stumble every single time you mash the pedal, not sometimes. And once it stumbles a couple times, check engine light pops on, and you’ll pull codes ‘bank 1 lean’ & ‘bank 2 lean’.

Doyoubelieve has the right idea. A lazy MAF sensor will make any truck a dog.

I understand your concern regarding dirty trans fluid, but I think that’s unrelated to your driveability issue