coolant loss

[servantsalesmen]

I have a real head scratcher here. Today my 04 sierra with a 6.0 started to overheat. The truck has 92,000 miles on it. I pulled over and at shut it off at about 245ish degrees. I let it cool off, opened the coolant res. And it was bone dry. The owner of the house I was pulled over at was kind enough to let me top off with water to get it home. The whole drive home I was running just shy of 210 like normal.

 

I have had this coolant leak issue for a while now. I'll give a little history. Trucks brake lines blew in may of 2013 at about 85,000 miles. It sat untouched until march of 2014. I replaced all the lines and got it going again. At that time the coolant res was empty so I topped it off. I drove the truck then all summer 2014 no issue until august of that year. The flexplate cracked and it sat parked again until December of 2014. When I got it running again, the res was empty so I topped it off. I drove it then daily with no troublr until about March, the heat stopped working, I checked and sure enough, no coolant in the res. Filled it up and drove no problem until today.

 

Now all that said, I have poked around the motor a tad to see what I can find. I found no visible leaks on the motor except from right around the harmonic balancer(which needs replaced, as the truck shakes like hell.) It looks to be oil. I also don't think it's head gaskets because if it burned over half a gallon of coolant in 2 months, I would probably notice white smoke. It does not smoke. And in the winter when it was out of coolant in the res, the engine never moved above 210. So the engine was holding it's coolant. And lastly, the truck does not leave any puddles or drops on the ground.

 

I need ideas on where all this coolant is going and how to track it. Thanks guys!

[ColoradoDave]

You might consider pulling an engine oil sample and have it analyzed for coolant content.

[Black02Silverado]

What does your oil look like? Any signs of leaks around the water pump? When it sat was it on pavement or bare ground to see if you can see any leaks on the ground.

 

Not sure if the 6.0 had castech heads or not but worth a shot at checking into.

 

 

Sent from my MaxiPad

[ColoradoDave]

While the year timeframe is right, this article implies the 6.0 does not have the problematic head (it mentions the 5.3 and the 4.8 as being the problem children).

http://www.agcoauto.com/content/news/p2_articleid/148

 

The article mentions several things to check in addition to the head issue and is a good read.

[servantsalesmen]

I think I may have just tracked down the issue. coolant res has a hose coming off the bottom of it and the cheapo clamp on it is loose. I'll replace the clamp and res today and I'll report back.