I am at 1500 ft in the NY southerntier and have as much salt as anyone. Don't have the way below zero temps though we do get to -10 occasionally. Doubt the salt issue was the culprit. If the motor blew out the exhaust at the same time the piston burped, could be a timing belt jump / backfire / detonation combination. And extreme cold does wonders for oil circulation upon first starting. Those temps actually require a block heater. Anyway, would bet on blown timing for the cause. If the truck has always been a salt truck, the sheet metal is probably on its way out if not already gone in places. Book on a 96 T around here is roughly 5-6 K for pristine condition. Choice is salvage parts or go to a rebuild ------ and is it worth it? eBay shopping has some nice T's for very reasonable prices. Got my 93 4x4, no rust, fully loaded for 3500........150k

One more NY thought. 96 and newer vehicles must pass emmissions testing. 95 and earlier do not. That's why both mine are / were 93's.