The oil calculations in the newer cars seems to be much better than the older systems. I've been told they calculate based on RPM, engine temp, exterior temp, and a number of other factors. My SS Camaro went around 10K miles on 8.5 qts. of synthetic and never had any issues after 81,000 miles. My Corvette gets about the same on 10.5 qts of synthetic. I just had the motor apart for a cam / heads / bottom end job at 75,000 miles and there wasn't any sign of abnormal wear (and I drive it hard). So, I'd just let the light come on and change it then.
I don't know exactly how true it is, but I've also heard that the newer trucks with a tow mode will change the calculations when towing to account for the increased load.
2012 Chevy Tahoe LTZ - HD tow package
2017 Rockwood 2703WS Emerald Edition