"Overdoing it " , I mean without rubbing etc...
This truck is mainly just used for hauling firewood ( I cord of stacked split hardwood at a time, with side boards on it) and hunting/fishing.
It gets used 3 or 4 times a month, that's it.
With all that weight the front doesn't sag much at all and I've got 2 extra leaf springs per side in the rear.
I "think" it will handle 33's when loaded with wood.
What you might want to do is get some leveling coils..and you might need to trim the bumper..depending on how much flexing and offroading w/ tight turns you do.
If what you say about your springs under load, 33 x 12.5 will fit. Just check out the clearance over the rear tires with a heavy load. If they are close, you may rub on a bump that jolts your tire. The only rubbing that you will get is with the front wheels on a hard over turn. :blush: