I've pulled a loaded car trailer behind my '55 1st GMC Suburban. GMC 270, SM420 and 3.08 gears under the rear.
With 70's vintage drum brakes on the rear and disks on the front, slowing it down without a brake controller can seem scary and I don't think I'd choose to do it again.
With my rear gears running 70+ on flat ground with an empty trailer isn't hard. But it sure can be slow to accelerate, especially once I get a load on that trailer.
