I've followed the various threads on this topic for some time and gone back into various archives via the search function. What a remarkable body of information on this topic! One comment that sticks out for me is from Idaho Doug and that is to the effect that these trucks, aside from wrecks, can only really get hurt from overheating. The tales about HG failure and the problems that can create are scary, but replacing the HG as a pm item is scary as well, unless of course you have the time and skill to do it yourself. My read on the topic though is that frequent radiator maintenance, preferably with Toy coolant and close attention to belt condition, fan clutch condition and the integrity of the radiator itself can largely forestall an HG issue. My impression is that even a temporary spike in operating temps can start the HG on the road to failure. For my own part, the coolant, belts and rad issues all seem to be under control. The only thing that jumped out at me was the fan clutch and I ordered a new one from CDan last week, strictly as a pm item. Before it arrived, we went on a 3 day trip from LA to Zion NP in Utah. The coolant and the thermostat in the truck were new, as were the belts and most of the major hoses, including the PHH. The truck , 1995, has 119K soft miles and I'm the original owner. For anyone familiar with the route on I-15, temps varied from 98 - 107 the entire trip. Baker was 105 on the big thermometer as we drove out of the valley up to Halloran summit (4,000ft). No issues with AC on #3, OEM temp gauge didn't move. Return trip, similar temps, 100F on climb from Primm up hill into California. AC blasting and cold all the way, no changes in temp gauge. When the truck had 80K miles, I travelled from Chicago to LA, pulling a 4,000# trailer in high temps for the entire trip, without any cooling issues. The moral, at least for me, is if all or most of the components are functioning right, overheating is not any sort of issue for these trucks. When I got home and saw the package from CDan with the fan clutch, my thought was to wait for some real indication of failure in the current one, before replacing it. I felt good about having it on my shelf. When I opened it up though and checked the resistance (to turning) that it had, it seemed very different from the one on my truck. I frequently check the one on my truck and while it does have resistance, my unscientific assessment is that the new one is at least 3 times as diffucult to rotate. How long might a marginal fan clutch slowly damage the overall system to the point where when its noticed, significant damage is already done? I now feel a lot more inclined to change my fan clutch tomorrow, rather than be smug about having a "spare" on the shelf.