So my truck has 104k on it and my friend drove it just around town one day nothing rough and then said it was loosing power and when they got home it was leaking collant through the resevoir line. I got there and tried to turn it over but it wouldn't so I have it some gas and it blew out a ton of white smoke and died. I ran a compression test on the spark plugs and it showed leakage so I tor it down figuring it was the head gaskets. Well just got to the heads and the gaskets are in good condition. Help please

 

Looking at the heads with a naked eye, you might not see the issues. Heads need to be pressure checked and magnafluxed for cracks. If not the heads though, only other place to leak is a cracked block.