Ford Repair: 92 Ford Ranger 4litre, Blows Head Gasket s, backyard mechanic, head gasket

Question
Since my 89 broncoII tranny kicked the bucket, My friend is offering me, at no cost, his older excellent body shape, non smoking or oilburning 92 ranger with a 4litre.
Here's the problem: The prior owner went through at least 1 headgasket repair that we know of. My friend then purchased a head and had it resurfaced/reconditioned then installed it (backyard mechanic). the head gasket lasted 4-6 months then blew again. My friend stated that he was rough on his driving and did not 'baby the truck'. I am not a hard driver of vehicles. I can have the vehicle and he will help me replace a new head gasket then transfer the vehicle to me. ....So why is this motor going through headgaskets? Should we use new headbolts? Is there an aftermarket fix to resolve this (continueing problem....IE: Caddillac dealerships have an aftermarket head bolts that are shorter bolts to resolve their headgasket dilemna) What are your suggestions? I am unemployed at this time and thus am motivated by necessity to do this job myself. He further stated that he probably just didn't do the torqueing exact. Respectfully, Dan

Answer
Hello Dan, If the engine has gone through at least 1 set of head gaskets I would be leery that the deck of the block may be warped. I don't believe that a 4.0L uses a torque stretch head bolt but it might in which case they can only be used 1 time after that they are "junk". You can take the heads off and check the deck of the block with a straight edge and a feeler gauge. If it is more than 2 thousands of a inch it is warped and get a gasket to seal right. Hope this helps Thanks Tony