88gmctruck's 1999 K2500 L65 mystery coolant loss.

[83GMCK2500]

Panic and rage #37 fixed, returning to normality.

 

[robzombie4551]

You also might want to check the radiator, the tank crimps can lose their tension from the hot and cold cycles and the rubber band that seals the tanks to the rad can weep and collect in the crossmember and not hit the ground unless moving.

The rubber bands also get hard and start to lose their elasticity and will start to leak, small at first and get bigger as time goes by if left undiagnosed.

I've had new rads with the crimp tabs not properly crimped, although yours might be due more to aged rubber cracked/hard.

Tanks also develop cracks that can weep at first before letting go all together.

Either way a pressure test is the best way to find elusive leaks. Good luck.


Sorry, I didn't read it through and see that you found the problem, my bad, maybe it will help someone else in the future.

 

[88gmctruck]

Yup, I'm fully aware of the crap plastic tanks. I checked it throughly when it was pressurized to 25PSI, no leaks there.

 

[DieselSlug]

Nice and easy fix, gotta love those ones!