There are lots of places for coolant to escape from. The coolant cap can look good, but hold only low pressure, not the 18 PSI it should. So when you ride down the highway it vents. You can zip tie a paper towel around the overflow hose to check for that or just buy a new cap. Stores rent/loan pressure testers, so you can pump up to 15 PSI and wait on the leak. Unlikely you have an internal HG leak as stated, it would have progressed to much worse by now.

 

Maybe I'll go an do that today just to see what's happening. I know of two leaks near the front of the HG's that I can see clearly. With 263k and no back up vehicle I'm holding off doing the HG's. However, I would like to tear into it and replace the HG's and see how long she goes for. It would be rather impressive if I she goes over 300k.

BUZZ, going back to your original question I figured if that were to happen it should have happened a long time ago. And if it did I'm sure she wouldn't be running as well as she is right now even with the leaks and a faulty O2 sensor and very high miles. She may just be "the exception" to the rule.

 

A little chocolate milk never hurt anyone right, good for the muscles after a workout?? I haven't noticed anything milky in the oil. It's always been very clean, no metal shavings.

 

Drove mine for a long time - it was getting quite loud. Did a head gasket job and when I first pulled the head off, it looked nasty where that leak was, but I cleaned it all up and there was no groove in either the block or the head surfaces.







Videos from before the head gasket job: