I don't know how heavy the load was, but the Blazer didn't like it! Struggled to get up to 60 mph, temp hovered around 230*, I got 9 mpg, and stopping was exciting. But it made the 500 mile round trip from my house to Oklahoma city and back with no major problems.

And, with all my brother in laws crap out of my garage, I can actually get the truck in there to work on it if I need to!