Hello, I have a 2017 Colorado ZR2 Duramax with 4 inch lift, 33 inch tires, delete with a mild tune. The problem I am having is while towing, even light loads, empty tandem trailer (<1500lbs) and a small camper which is a 16 ft end to end ultralight, my Colorado will lose power and start stuttering, it occurred while on a trip with my camper a couple of years ago and went to the point the engine was running poorly and couldn't pull any more so had to pull over. When this occurs the stabilitrack warning comes on and if I keep going will throw a engine light but none of them check out. Stopping and turning off the truck for a few minutes or even an hour clears all lights and warnings and the engine tends to run normally. This weekend while towing my trailer with a couch on it, it began to do this again. I seem to have no issues on short 15-20 minute runs with the trailer loaded but "gets tired" if I am pulling with any weight on it. I thought I had this problem licked by changing out the trans fluid and flushing it and replacing it with Mobile 1 HD HVT trans fluid or whatever they call it that many on here advised and it did stop the normal shudder it had while driving without a trailer. Nice shifts and smooth after changing the fluid. I have an aftermarket trans cooler and the warmest I have ever seen the ATF is 165 degrees while towing. However I was advised if the TC got glazed by the wrong fluid that was put in by the factory it could be causing the issue. I have asked several people about this and have had varying ideas on the subject. Weak injector, bad sensor, clogged fuel filter (gets changed every 2 oil changes), diff issues, etc...etc. Could this be a bad torque converter or maybe timing belt? If so it seems weird it has held on this long (over 2 years) if it is. I have had many issues resolved by using this forum and has saved me a ton of money but this one has me baffled. It just turned over 100K and is not abused and runs about as perfect as a Duramax can. Again, had many issues, have worked through them all and this one still persists. Can anyone shed some light on what this might be or where to start. I will answer any questions as quickly as I can. I appreciate the help. Thank You.