I have a bit of a coolant leak that seems to be the HG. The truck goes thru a 4L jug of coolant in about 2 months of regular use and went thru more on a recent road trip. You can notice it in the exaust on cold mornings. So now I check the coolant levels almost every day.
After the long trips and every once in a while I find the rad isint sucking in any of the res and I have to fill the rad back up.

Anyway truck runs fine so I kinda have been putting off dealing with it, but cant help wondering if I am damaging it beyond repair?

 

Yes, you are destroying the engine. Water in the oil is very bad, as is coolant sitting in cyl (pits the walls.)

If you've been going this long you've likely done enough damage that it needs a complete rebuild or a swap to a better engine.

A compression test will tell you the state of the cylinders, but only a teardown will show you the bearings.


If it were me, I'd run it w/ bars and stopleak, meanwhile I'd be gathering the parts for the upcoming death of the current motor.

 

Compression is good, 150 - 155 all around. Oil and coolant both look normal. Oil pressure has always been on the lower side.
Been like that since I got it from the PO...so may as well just drive it till it dies and swap the engine later? Or is it a lost cause to try and salvage mine.

 

Head gasket failures are not all the same. The HG has adjacent oil passages as well as coolant passages next to each cylinder. Depending on where the gasket fails you may experience water/oil problems, over pressuring the cooling system and so on. I would NOT put any stop leak in the cooling system. Its rare that stuff works and may trash the radiator and heater core. Given where you live, drive it but check the oil and water daily until warm weather. Also, remove the valve cover oil fill cap and watch for condensed moisture in the morning before start. When you see beads of moisture on the underside of the cap, DO NOT run the engine any more or you will trash the bearings and more.

My $0.02