I've never heard of tires alone being the cause for a warranty denial.
Think about it this way, though. Larger tires put much less load/stress on the driveline than a 7,000LB trailer. Towing a trailer doesn't void the warranty, larger tires shouldn't impact it either (unless the tires literally damaged the truck because they were making contact).
That’s a good point. I’m probably overthinking it!
2017 Chevy Colorado CCSB Z71 4x4 - Zone 1.25" Level - 265/70/17 Falken Wildpeak AT3W