we only got 125k out of the 94 5.7 2500 GMC pickup my dad has.
Granted, the ream main seal blew out on the hwy, and roasted the motor in an instant.
We threw in a 95 5.7 with 60k motor in it, and its been fine since. I think the entire vehicle has 200k on it now, so, the motor has 100k on it.
I got over 400k on 2 different 86 ford broncoII's both with the 2.9 v6. The motors were original, but both had replaced auto trannies, 1 each at some point.
The eddie bauer 86 I had had over 450,000 miles on it when a drunk t boned me when he blew hi stop light and destroyed the truck. I was unscathed, I got like 3300 dollars from insurance for the truck, which IMHO was a lot more than it was worth. Had that accident not happened, I guarantee it would have gone 600-700k.
I have not had that great of luck with GM products, although I got 250k out of a quad 4 91 Calais (grand am) with only a head gasket in there at 65k, and a solenoid in the tranny at 150k, besides normal wear items exhaust, tires, brakes, fuel pump.