I ran a 4spd behind an SBC for over 10 years. No trans problems at all. California deserts, mountains P4W Round Up, Sierra Trek, HDR etc.
Keeping drive shafts together was a whole other story.
Luckily I live in a place without EPA compliant nozzles. Still, all my jerry cans are old enough to say Made In USSR on the side. New gasket for the cap and they work perfectly.