I have an '03 KR CC DRW 6.0 TD. I have a stock motor and run SCT performance tune, MBRP cool duals.

When I am pulling my RV (18K lbs) the coolent resiviour overflows like the engine has over-heated. My temp guage indicates normal - in fact once the truck gets up to temp it never moves.

Could my coolent resivuoir overflow be from:

1.) Excesive pressure (engine taching 3,000 RPM)
2.) Engine overheat problem
3.) Stock guage is junk and I should get after-market guages

 

I'm sure others with a lot more smarts than me will chime in shortly but sounds like EGR cooler. My 03 did same thing only when towing 5th wheel. Dealer replaced both engine oil cooler and erg cooler. Hasn't done it since.

 

so as i read your post it seems like you tow 18k lbs with a SCT performance tune and don't have aftermarket gauges. is that correct? if so i think you will be lucky if its just a EGR cooler because it could be head gaskets.
give us some more info like how much coolant you are loosing and if it happens all the time or just when you are towing.

 

no disrespect but after re-reading your post i have to ask something:
IS THIS POST A JOKE???

 

Under normal conditions going to 3k, should not be too much for the engine. However it could very will be high cylinder pressure(which causes headbolt issues eventually and what is probably the case here and is a known problem on the 03 6.0s)

It could be an engine overheat problem, or it could be(and probably more then likely) a head bolt problem. You can have blown heads and it still run normal engine temps though, so you actually should rely on other tall tail signs of headgasket problems(leaking coolant out of the bottle, tea kettle noise etc).

I would advocate that even if you didn't have a tuner especially since you are towing with the truck and it's not just a daily driver, but since you do have a tuner that I would actually say it's a requirement at that point.

 

I am not sure if this bit of info is in the tech folder. I can watch an assortment of data on the odometer. Press and hold the trip reset button on the dash and turn on the key start the truck. Release the button. Display changes to a gauge self test then you press the trip button once to step through the data points. One is the water temp in deg C. I used that before I had a real gauge installed. I still use it to check the actual temp used by the PCM to validate my external gauge installed on the water bypass filter.
I read some where- a list of what all the data points mean. Some are in the clear and easy to use, others??? no clue.

Is that 'user tip' and list posted on the tech folder? I could not find it.

I never saw the stock water temp gauge ever move once it heated up. My AM gauge does change as I drive.

 

The problem only happens when towing, and only when pulling steep grades.

This question is not a trick.

I loose about half of the contents of the coolent resiviour when this happens and it is sprayed through the "radiator cap" on the resiviour.

Head gaskests: Is once blown always blown? How can I breech the seal of the head gaskets under high cylinder pressures and have then seal during nominal loads? Makes no sense to me.

EGR cooler: If I disconnect the EGR connector, will EGR possibility be eliminated as a root cause?

I have SCT program with stock guages - I ran out of funds due to frickin diesel prices !!! My stock temp and tranny guages do not change during the time I pull steep grades with the big 5W in tow. Will short spikes in engine temp show up on the guages? How much historisis or averaging do they have?

Is the turbo cooled through the coolent system. Could high EGTs boil or push out anti-freeze?

 

Yes, unless you machine the heads flat or replace the heads with new flat heads, rather or not you use ARP studs or regular stock head bolts, you'll get head problems down the line. Breaching the seal has to do with engine load as well. Higher the engine load, higher the pressure causing the head bolts to stretch and there you go.

Taking care of the EGR valve in the up-pipes will eliminate the egr cooler as a possibility for future problems(and it will happen sooner or later). Just be careful with whomever does your by-pass in the up-pipes as that could cause you to have an exhaust leak and those are not cheap to repair, nor is it fun to drive with a lack of power.

Stock gauges won't even tell you when your getting close to the danger zone on any of the temp gauges. The gap between the different movements on the stock gauges is huge. I would take the SCT off and wait until funds allow for aftermarket gauges(or atleast an OBD-II digital gauges, such as scan gauge II, which I believe does everything but egts), as the tuner is exposing problems that you are having. It may or may not have caused those problems, but it is at the very least exposing them to you.

The turbo runs the the low oil pressure system. EGTs help to determine engine load, which is a factor in head gasket issues as that translates into how much cylinder pressure you have in there which is directly related to headgasket issues.

 

Thanks for all the feedback

It helps me understand the dynamics of the 6.0L.

On the topic of stretched head studs, can periodic re-torquing the head nuts help compensate for the flex in the studs? Seems like if the studs stretch a few thousandths a simple re-torque could by time.

I will revert back to the stock tune for a while to see if this will reduce my issue and support the hypothesis that high cylinder pressures is pushing out the coolent.

BTW, I have been working with gas motors for decades (Mopar-or-no-car!) (Mopar to ya if you can keep up!) I can tell when a gas motor is running hot.

But with the 6.0 TD it seems to be something else than an overheating condition. If the seal is leaking on the heads and pressure is getting into the water jackets in the form of air, this would simulate the over heat condition. In all the years of building Pro-Streets I never blow head gaskets, so I am not sure what the symptom would be.

With an overheated gas motor, one of the symptoms is poor throttle response and "flat" performance and power loss. The 6.0L TD still feels like it can pull every house in sub-division at the same time - the motor pulls hard and runs well dispite the "leak".

 

I would doubt that would help any if at all. If it truly is leaking right now, then more then likely your heads are warped, even torqing them back down, they are still warped and it's not a good seal.


Unlike head gaskets being the death knell to gas engines, people can drive diesels and pull loads with blown heads and just refill the reservoir as needed(yet I wouldn't advise this, but it can be done). Diesels are just different animals from gas burners.

 

Mine did that, only when towing my 5er. And it turned out to be HG's and egr cooler.