Coolant keeps disappearing?

[rolfsent]

So my 1997 Yukon has been been losing coolant lately and I'm not sure where. Today I noticed spots in the driveway in two different places so I checked the coolant again and for a second time the coolant overflow is completely empty. I've never had any overheating issues and I just towed my camper 200 miles no problem. Temp gauge never gets hot. I checked the oil too, not a problem there either. Only the small spot could possibly be coming from the bottom of the radiator and I have no idea about the big one. I let it run till it got up to temp and couldn't spot any leaks or drips. Any ideas on where my coolant is going?

 

[nobsobs98]

Are you checking the overflow when hot?

 

[rolfsent]

Are you checking the overflow when hot?

After driving it around it went up to less than halfway to the cold line

 

[99_Yukon]

Mine was actually leaking out of the water pump. I never overheated or ran up the temp gauge. But my overflow bottle was always empty. New water pump for me, no issues since.

 

[Tbruz]

You can "purchase" a radiator pressure tester from the auto part stores.
You purchase it on a credit card and they credit back the entire purchase price when you return the tool; if you don't return it you bought it!

Pump up your system to around 13 to16 lbs when the truck is cold and you can crawl all over/under and see where and if you have a leak.

If no obvious leak you may have the notorious leaking intake gasket issue.
Pull the plugs and see what they look like.
Tbruz

 

[craz-28]

Well, just going off of the picture alone, you probably have a crack in the plastic jug(s) on the radiator. They are notorious for cracking. From my past experience, you probably have a small crack on the backside of the jug, the pressure is spraying your radiator support and its running down and draining on the floor.

Testing your pressure is a good idea, but sadly I think your going to find that you've got a crack or its leaking where the jug meets the core on the radiator. Now remember I'm going off your picture alone but if you had any of the other issues, your leak would be more centralized under the truck and not dropping from under the bumper.

 

[willxfs]

I've had a couple of coolant leaks over the years. One was the plastic tanks on the side of the radiator, one was the quick connect coolant hose on the front passenger side of the intake manifold and the last was the heater control valve. I also lost coolant before I changed out the lower intake manifold.