1999 3.0L V6 about 157000 miles
Here are the symptoms
*Temp gage rises quickly after 2-3 miles of driving, goes about 3/4 up then levels off about 1/2 way
*Coolant fills the overflow reservoir and once even "puked" and overflowed with pressure
*bubbles in the overflow reservoir almost as if it were boiling
*with cap off, I rev the engine and see bubbles in the radiator
*with engine cold I check the radiator it needs fluid after each time I drive, but I think most of it goes to overflow reservoir
*cold engine coolant pressure check, I pump it up to 11lbs, it does not hold pressure, needle on my gage drops slowly and immediately

I get heat and the engine seems to run well. I do not see smoke/steam out the exhaust and no external leaks. I have yet to do a compression test.

Before I tear down, is there any thing else I should check or any other problems I am overlooking?

Bill

 

I would do a compression test to confirm but based on your symptoms it sounds like it is a blown head gasket.

 

Welcome to the forum

Do the Glove test, posted here: https://www.ranger-forums.com/4-0l-o...eating-151923/

You can even find out which cylinder is leaking