Make sure your cooling system is up to the task. The biggest killer like
@tagexpcom brought up is heat. Fresh coolant in the radiator and surge tank before any tow trip. Make sure all
Your hoses and belts are in good order. No leaks or cracks. Make sure your water pump is not leaking coolant or water. And if you haven’t already I’d highly suggest upgrading your transmission oil cooler. If you have max tow option on your Tahoe, it will have a factory added transmission oil cooler mounted in between the front grill and the radiator. It works but it’s timy. That 6 speed trans behind your 5.3 is going to be working hard pulling the weight so it’s going to see some higher temps. Heat kills transmissions! Many guys here are running the trucool 40k max cooler, myself included. I tow a speed boat up and down the mountains where we live to the flatlands down below a couple times a year and the only time I see temps above 150 is when backing the boat into its winter parking spot behind a gate with a long narrow corridor so it’s slow and steady backing and maneuvering. All other times my trans stays cool and the minute I get airflow going through it after the backing, it cools right back down.
Many options for trans coolers and many ways to mount them and plumb them in, detailed in the subforum engine and drivetrain section under your trucks year range, that the search feature will bring up should you choose to research it. Along with should you choose to upgrade the cooler, there will be many recommendations and links to purchase a cooler.