I have to pull the head off of the truck soon. I have been getting air in the coolant system, so I ran a tester on it and the indicator fluid shows that it is definitely exhaust gases. I am going to run a leak down test before I pull them just to see if there is any indication on which cylinder MIGHT be the cause. I am hoping for a head gasket replacement only, but who know. Could be a cracked head as well. Truck never overheated.

The head gaskets were new when I put them in, and have about 70,000 miles on them.

My question, is there an alternative to special tool 8515 to hold the secondary timing chains in place?

And since this is the second time I am pull the heads, I am guessing that new head bolts are a good idea? The first time was when I pulled them when I swapped the engine in.

Thank everyone.