I have started losing coolant at a rate of half a gallon every 10 days. I have no visible leaks. I always have the smell of coolant around the truck. My coolant bottle now is picking up what appears to be oil spots. Dealer is stumped. Put a dye in the coolant to try and track loss and have had no luck. Any help appreciated.

Engine oil cooler is likely leaking, exchanging oil and coolant at a small rate depending on which has the higher pressure at the time. The coolant the burns off inside the engine due to the high temps the oil sees.

Tell your dealer to replace the integral oil cooler.

 

2005 chevy dually duramax:
I just had my truck modified with race heads, turbo, PPE programmer, and single fuel system and Suncoast tranny with 6th gear added and its doing the same thing but now my truck is overheating. My mechanic who modified it says its the pressure of the engine is so high when U hot rod the truck it blows coolant out thru the overfill tank. My overheating issue he is going to look at tomorrow.

 

2005 chevy dually duramax:
I just had my truck modified with race heads, turbo, PPE programmer, and single fuel system and Suncoast tranny with 6th gear added and its doing the same thing but now my truck is overheating. My mechanic who modified it says its the pressure of the engine is so high when U hot rod the truck it blows coolant out thru the overfill tank. My overheating issue he is going to look at tomorrow.

If it is blowing coolant out thru the "overfill tank" thats because it has a blown head gasket. Now, if you have been losing coolant in this fashion and see the temp go up as in overheating thats because you are low of coolant, good chance you will warp the heads. If your mechanic does not know this I suggest finding a new mechanic, he may have already cost you that engine.

 

"the pressure of the engine is so high when U hot rod the truck"

Yeah, I would like to know what he means here. The coolant system is a closed system from the rest of the engine. If there is pressure getting in there from the engine, I agree with Tx that the head gasket must be blown. Good luck with your "mechanic"...

 

same here

but finally i found the leak at the water pump.....

 

I have the same problem though mine is not as fast of loss and I dont really notice a coolant smell around the truck. About every 60 days my overflow tank is low and I start getting low coolant messages in the mornings. After I run the truck though the messages stop. Sofar I haven't been able to find the leak, but I will definatly have the integral cooler looked into.

 

Mine is losing coolant also. Having to add about every 2 weeks. Dealer has pressure tested twice and says there is no problem. If it were the oil cooler, wouln't that show up in a pressure test? I don't think there is any oil in my coolant and I haven't seen coolant in my oil either.

 

I have similar problem with an 01, anyone figure it out yet? I noticed that even when its cooled down when you open the cap it has a lot of pressure in the system.

 

Mine was the water pump leaking, couldn't see any on the ground. Crawled under neath and sure enough there was a clean spot up by the water pump. Had it fixed under warranty.

 

I have similar problem with an 01, anyone figure it out yet? I noticed that even when its cooled down when you open the cap it has a lot of pressure in the system.

You have a blown head gasket my friend. Get it fixed before you lay waste to the heads and cost yourself BIG BUCK$

 

get it fixed before you get coolant in the oil and spin a bearing