I've been busy with work since I got back so I haven't had a chance to go at it as much as I'd like to. I've got around 140k on the truck right now, but I am convinced the original WP failure and subsequent overheating was really a fluke. The second overheat I have yet to figure out why it occurred. I did a compression test on the motor and all cylinders seemed to have fairly good compression (all were around 165-170 psi) so if there's a leak in the HG at all it's definitely very small to say the least. I also looked at the plugs and they all looked to be burning fairly well (again no obvious signs of an HG leak). I'm going to pull the thermostat completely and see if the truck is still pushing coolant out of the radiator neck quickly and then let it heat up and see if it boils the coolant again. I doubt the thermostat is the problem since I drove it for 40 min to an hour before it overheated the second time (either a bad thermostat or an air pocket in the cooling system should have shown up much faster than that). If it is a headgasket leak then it is indeed very small because there's no smell of coolant in the exhaust (definately nothing visible). I might also try just taking off the valve covers and retorquing all the head bolts and see if that doesn't help my issue without having to redo the HG. I'll figure it out now that it's off the road as a DD (I got my wife a new 2007 CRV EX AWD to drive around in so she's set and then it will be up to me if I want to drive the 4runner or the Civic).Originally Posted by mkgarrison5