nothing like what you guys have but it has towed a lot of cars we just recently upgraded to a tow-dolly, i actually haven't even used it yet but my brother has put some miles on it.
My father has over 170k HARD non-maintained miles on his '93 Chevy conversion van. Has pulled an enclosed car trailer (about 4k by itself) from here to Las Vegas, NV with a '57 Nomad in it

BEFORE he had a trailer brake control! I don't know how that van has lasted so long, it's never had a tranny service done, plugs have been changed maybe once around 8 years ago when I did the airfilter, cap, rotor, wires, plugs. If he's moving things around town he still uses it!
I just picked up an '01 F250 a little over a month ago (I know, I know, but I did go 18 years of driving without ever actually owning a ford)
Had 111k miles, Banks IC, Banks Bighead wastegate & turbo housing, Banks 4" turbo back exhaust, ATS transmission & converter controller, ate intake, a pacbrake exhaust brake & bully dog programmer. Gets better MPG than my '97 Z71 I had & it has absolutely no problem pulling a 7700# (empty) toyhauler. Oh, and I don't have to worry so much about breaking an axle every time I go off road like I did in the chevy.