[patricktucker777]

03 5.9 Cummins six speed manual 4x4 dually... Bone stock had it about 5 years never moved the temp needle Previous one owner 90k mile from an older neighbor that passed. His wife had every recipe from day one kind of truck. He babied it and was immaculate when I purchased. Recently when pulling heavy loads over hills 12k lbs 5thwheel will get hot. My live feed gauge shows hottest 235 then I would pull over and let it rest. This happened on one trip then I took her home and changed the fan clutch with OEM and the radiator... I put in a aluminum radiator it is better but when I pulled heavy today I reached 225 never seen any thing over 205 until what ever is going on now Currently I have 190k miles, I have no oil in the water, no water in the oil and no water coming out the tale pipe, no drop in water fluid in radiator or reservoir. So I've ruled out head gasket. I have no oil in the radiator is it possible that the engine oil cooler is the culprit? If I'm pulling straight aways or empty needle never moves only steep grades while heavy... Any input would be great

 

[Cooper21]

Test the thermostat. If it’s not opening change it.

 

[David_411]

Is the engine fan engaging?
It's very loud and you should hear it roar.

Change thermostat. Only use OEM Cummins.

What gear are you trying to pull the hill in?
Let engine rev 2200-2500rpm. It lowers EGTs.

Seems to be common to hear people lugging their engine which is awful for thermal management.

 

[coolbreeze]

Gear selection on hills makes a huge difference in engine temp assuming the cooling system is in good shape.

 

[Red and Black]

Changed the fan clutch and radiator, and thermostat(s) were not on the list?

I assume all the coolers, etc in front of the radiator are clear?

 

[patricktucker777]

management

Thank you for your input

I just put a new OEM fan clutch from dodge in and yes it is engaging

I changed the water pump and t state from Cummins about 3.5 years ago 75,000 miles I can change them again. Cummins recommended to me 190 at the time I changed it last time. Is that what your thoughts are?

I pull hills in 3rd or 4th gear depending the grade and 2200 - 2800 is my range I sit in

Lugging happens from time to time but is minimal...

Something seems to be off since it is a new occurrence and the driving habits are the same as the last 80,000 miles on the truck with out this issue.

 

[patricktucker777]

Changed the fan clutch and radiator, and thermostat(s) were not on the list?

I assume all the coolers, etc in front of the radiator are clear?

Yes the inter cooler and ac radiator we're cleaned thoroughly with radiator cleaner foam that pushed almost all the dirt out and carefully cleaned with pressure washer from a far-rest not been the fens. They seem to be very clean now that was not the case prior to cleaning.

The fan and radiator were changed last week the t stat and water pump 3.5 years ago 75,000 miles. OEM Cummins parts were used I could changes them if it is needed. Very easy job on this truck

 

[Big Lar]

I may have missed it but have you checked the water pump,oem original?
How are your brakes doing, any drag?
Larry

 

[seafish]

Sounds like you’ve done everything bout right and that includes what other members are recommending.

That said, I Haven’t seen anyone mention actually checking the coolant level in the radiator yet…😮

I am saying this NOT because anyone here is dumb, but because the ONLY time my 2005 has overheated is when I didn’t catch a small leak in one of the difficult to get to block to heater hoses and eventually enough coolant leaked out that it began to overheat towing 12k up hills. Even with the fan engaging properly, there simply wasn’t enough coolant to allow sufficient or efficient heat transfer through the radiator.😳

 

[patricktucker777]

I may have missed it but have you checked the water pump,oem original?
How are your brakes doing, any drag?
Larry

That is a great question I do have some brake drag going on it is slight but it is there. I took it to to shops that both thought either caliper or wheel bearing. Wheel bearing felt fine but since I was in there put a new temkin hub assembly and new caliper. Wheel drag still persisting... Thought line collapse but when bleeder is open it doesn't resolve the issue.... I tried 3 calipers because they assured it was the caliper... The chance of 3 bad ones is fairly unlikely...

Could the Master cylinder be sticking? It is mainly the driver side that was sticking that's why I had ruled out master cylinder... Do you should think that the lite brake drag is contributing to the over heating?

 

[patricktucker777]

Sounds like you’ve done everything bout right and that includes what other members are recommending.

That said, I Haven’t seen anyone mention actually checking the coolant level in the radiator yet…😮

I am saying this NOT because anyone here is dumb, but because the ONLY time my 2005 has overheated is when I didn’t catch a small leak in one of the difficult to get to block to heater hoses and eventually enough coolant leaked out that it began to overheat towing 12k up hills. Even with the fan engaging properly, there simply wasn’t enough coolant to allow sufficient or efficient heat transfer through the radiator.😳

I just changed the radiator and filled and burped the system I believe it is full

 

[Big Lar]

With my truck in Illinois with all the salt and whatnot I get problems with the glides sticking due to moisture getting inside the rubber boots, which causes the brakes to drag, ie the brakes won't release properly from the disc usually by the end of winter.
Every spring I check them and replace and cleanup what's needed. It's worth checking them.
Larry

 

[patricktucker777]

With my truck in Illinois with all the salt and whatnot I get problems with the glides sticking due to moisture getting inside the rubber boots, which causes the brakes to drag, ie the brakes won't release properly from the disc usually by the end of winter.
Every spring I check them and replace and cleanup what's needed. It's worth checking them.
Larry

I put in new caliper (3) different ones in fact for my concern of slides sticking... But the likelihood of 3 bad ones is rare... But I still have a little drag. Any other ideas what would cause the brake drag

 

[Big Lar]

Well I'm certainly no expert like some of the guys here but a warped disc comes to mind, like I said above could be rust in the glide boots, also could be rusty,dirty where the brakes sit in the housing.
I take it you don't have an abs code right?
Larry

 

[patricktucker777]

Well I'm certainly no expert like some of the guys here but a warped disc comes to mind, like I said above could be rust in the glide boots, also could be rusty,dirty where the brakes sit in the housing.
I take it you don't have an abs code right?
Larry

Yes I thought warp disk as well but the drag is consistent as I turn the wheel. If the dis was bent would get easy as I turned the wheel.

No abs light.

I appreciate the input

Have a nice day

 

[BFD]

Check the thermostat in a pan of water on a stove. I don’t even trust the Cummins thermostats much past 60,000 miles… I’ve had them fail that soon. The Cummins thermostats open about 5/16 inch if it’s working good.

 

[patricktucker777]

Check the thermostat in a pan of water on a stove. I don’t even trust the Cummins thermostats much past 60,000 miles… I’ve had them fail that soon. The Cummins thermostats open about 5/16 inch if it’s working good.

Thank you for the info and if 60 k is all they last I'll just change it I know I have 75 k on it... I figured they would last longer than that. I had a genuine Cummins in there 190 degree is that what you would recommend... One guys was saying 180 another said 160 but 190 is what Cummins recommended for it and what I have in there now

 

[BFD]

Check it first, so you aren’t just guessing. Use the temperature that’s recommended. If you have a problem that’s causing overheating, a different temperature thermostat isn’t going to do any good.

 

[slowmover]

Insurance I’ve used 20-years:
RMI-25

A similar product is SCHAEFFERS #258.

What’s to know is that only a film of interior mineral build-up significantly degrades heat transfer.

— Another avenue is an exhaust system blockage. Bent pipe or failing muffler.

Almost anything that causes higher fuel burn from optimum for a given state needs to be checked. This includes sticky caliper, alignment, air & fuel filters, CAC hoses, steering gear, etc.

A problem from big block carbureted gasser days was incomplete fan shroud and/or “air dam” underneath rad crossmember such that air was flowing in a circle over & over thru the radiator.

Fan blade clearance is a thing: how far out they extend from the shroud and the blade-tip clearance to the shroud itself.

The trailer also needs to be checked for axle alignment (1/4” out not acceptable), brake drag, and bearing pre-set.

Don’t forget faulty gauge.

 

[misterfixit_sd]

Low boost from a stuck waste gate?