I have a strange coolant issue. I had the low coolant light come on the other day in my 2007.5 LMM. I added aprox. 1/2 gallon of coolant to the overflow.

I borrowed a pressure tester from one of my buddies. The system doesn't hold any pressure at all. I have not lost any coolant since filling the overflow.

Is this safe to drive? What do you guys think? EGR cooler? headgasket? I have no coolant on the driveway, and I cannot see anything in the engine bay, skid plates etc.

Thanks in advance....

I have a strange coolant issue. I had the low coolant light come on the other day in my 2007.5 LMM. I added aprox. 1/2 gallon of coolant to the overflow.

I borrowed a pressure tester from one of my buddies. The system doesn't hold any pressure at all. I have not lost any coolant since filling the overflow.

Is this safe to drive? What do you guys think? EGR cooler? headgasket? I have no coolant on the driveway, and I cannot see anything in the engine bay, skid plates etc.

Thanks in advance....Very good possibility that it is the egr cooler. Had to replace mine on my 2007.5 at about 60,000.

EGR cooler is the most obvious first look, but were I doing it, I'd be questioning my coolant pressure test result. Hard to reconcile a truck running ok with no coolant loss and no pressure. No pressure would mean overheating and/or dramatic coolant loss. ??

EGR cooler is the most obvious first look, but were I doing it, I'd be questioning my coolant pressure test result. Hard to reconcile a truck running ok with no coolant loss and no pressure. No pressure would mean overheating and/or dramatic coolant loss. ??

Yes, I am confused on this as well. It really doesnt make any sense. I tried a different pressure tester with the same results. I guess I need to beat on it a little and see if the coolant loss is pressure related?

Do you think its worth doing the EGR cooler delete? I have had the blocker plate in since about 500 miles. Is there anyway to bypass the egr cooler easily?

Will it hurt the truck to drive it with no pressure in the system? I live in Florida and its been very hot these last few weeks.

Thanks for the help,
Patrick

Danville Performance has an easy to install EGR delete kits which eliminate the cooler and all the valves that obstruct the intake. You can see it installed in my Avatar photo. I got an increase in mileage of 1.5 MPG when I installed it. You will need to get a tune to turn off the CEL's. Of course, removing the EGR cooler voids the warranty.

When your truck is running at operating temp, is your upper radiator hose firm? If it is, your coolant system is under pressure.

No, the upper hose is not firm.... Going to buy that kit and go from there. Thanks

You should track down the leak before spending money. An oil analysis is a good idea to check for coolant in the oil.

The heater hoses at the cab can leak and vaporize off the turbo.

Are you using a pressure tester that goes down into the overflow bottle far enough to close off the vent hose. If not you need to pinch the vent hose thats near the top of the overflow/fill tank.