To all people who have a 2.7 motor with more than 160k on it... MAKE PLANS TO CHANGE YOUR HEAD GASKET...SOON!!! Mine just blew at 170k. I've been hunting around the forums and it seems the 2.7's head gasket goes between 160k - 170k. Like clock work...
What happened to me was the gasket went where you can't see it and filled the #1 cylinder with coolant. When I went to start it was hydro-locked (coolant in cylinder - piston can't compress the water). It didn't toast the motor (I hope) so what I'm doing is rebuilding the 2.7.
Just giving some heads up for all of you who think (like I did) the 2.7 will last forever without doing the head gasket.
I am @ 175k and so far so good, I have been on customs tacos for while now and I have not seen any mention of a head gasket problem on the 2.7L. Thanks for the heads up more fuel to convince the wife I need a new Taco.