# lil help with on overheating 6 litre chev.



## snowcrazy (Nov 18, 2010)

Well, Ive had problems with this truck getting hot under transport ever since Ive put the plow on it. This truck is a 2004 6.0 litre gas truck with a snow dogg ex85 plow.

When it first started to overheat I did a search here and it seemed that the extra heavy duty clutch for the fan was the answer. I got one, didnt do the trick

Next I bought the plow flow master spoiler deal. Tried setting that thing in several different positions and simply no results.

Soooooo I decided to have some electric fans installed. I thought that for sure would be the answer. I use a toggle switch to turn the puller fans on (clutch fan still mounted)...... those fans don't have hardly enough pull to make a piece of paper stick to the front of the grill...........

Heres the deal, once it starts to get hot I pull over and temp is around 240-250........ I sit for a minute while truck is running and finally the clutch fan will come on...... The temp guage drops to 190 within a minute............ 

No matter where I angle the plow, up or down side to side I just cannot get the air to blow through the grill to get the hot air to the front of the spring on the clutch fan.

The vacuum that is created by the plow is rediculous. Here is how i found this out. The beginning of winter I put plow on just to make sure everything was working correctly. I was driving down the road and noticed a steam of some sort being sucked OUT OF THE GRILL, AND UP AND OVER MY TRUCK...... absolutely none of this got on my windshield!!!! I stopped at the gas station thinking radiator hose. Under inspection I realized it was an air conditioning hose that blew and it was refrigerant liquid that came out the grill. Where the hose gave out was well back in the engine compartment and the hole wasnt even facing out the front of the grill. It just got SUCKED out.

Today, just for giggles I turned on my electric fans and placed a mcdonalds receipt out on the grill........... at about 40mph the receipt flew up and almost levetated above the plow for a second and then poof! blew right over my truck which tells me thats what the air is doing.

Ive tried so much and don't know what to do next. I know there is no restrictions with anitifreeze etc because if and when the clutch fan does come on the temp drops like a rock to normal but down the road I just can't get any air through the radiator.

any advice would be awesome. I thought about just putting a stationary mounted fan on it. No clutch just when the truck is running the fan is turning with the speed of the engine. Im just scared this is going to EAT my fuel mileage!! But it may still be a better solution to torching a motor......


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## beanz27 (Dec 22, 2012)

not sure if it would work, but being a ford fan myself, (fords are better and sit higher), maybe a lift would do something? That way you'd lower the plow more.


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## mpriester (Oct 2, 2011)

it is the fan clutch. do a search on here and you will find the exact part number needed from gm.


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## dieselss (Jan 3, 2008)

i have heard that a plow deflector works as well
not 100% sure but isnt there another fan as well as the clutch??
can look into a colder thermastat
assuming you cked the front of the rad, condenser, and everything up front??
when was the last time you did a total system flush??? like pull off all the hoses and run a garden hose in there??


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## theholycow (Nov 29, 2002)

I would consider not using a fan clutch at all, just a locked fan that runs at whatever speed the engine runs. As I understand it, clutch fans don't run full speed even when engaged.



dieselss;1589278 said:


> can look into a colder thermastat


Sounds like his truck is plenty hot enough to open any thermostat already.


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## dieselss (Jan 3, 2008)

But a colder tstat will open sooner rather than at 200 or whenever its set right now


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## Greenstar lawn (Jan 18, 2009)

My 04 2500hd just started having this is this yr with the plow on. I put a new water pump, thermostat, and fan clutch in and it still will have over heating issues. Never had this problem before with it. Also for some reason my fan is rubbing against the shrout


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## dieselss (Jan 3, 2008)

Fan on the shroud is b/c your motor mounts are bad. Replace them ASAP!!


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## Greenstar lawn (Jan 18, 2009)

I tried to look for them but couldn't find them. To replace them do it have to jack up motor?


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## dieselss (Jan 3, 2008)

Your motor mounts?? You can't find them?? 
Gotta jack it up to replace them yes


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## Greenstar lawn (Jan 18, 2009)

Well I should of said I couldn't tell if they were bad or not. But the fan is rubbing on the passenger side of shrout.


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## snowcrazy (Nov 18, 2010)

theholycow;1589385 said:


> I would consider not using a fan clutch at all, just a locked fan that runs at whatever speed the engine runs. As I understand it, clutch fans don't run full speed even when engaged.
> 
> Sounds like his truck is plenty hot enough to open any thermostat already.


Thats what Im looking into doing is the locked fan but scared of what that will do to fuel mileage.... I love these trucks for sure but ive known a lot of ppl having trouble with overheating with a plow on the 6.0 chevys......

Do you think fuel mileage will get hurt having to spin that fan ALL THE TIME instead of a clutch type.. I sure would think so...... Be better than torching a motor is my thinking.


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## dieselss (Jan 3, 2008)

Yes fuel mileage will drop. But your plowing so what does it matter?? And maybe a little give and take,,,,mileage verses overheating??
Green shoot me a pm


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## theholycow (Nov 29, 2002)

I don't think fuel economy will be affected in any way you can actually notice in your truck with the work it does. I suspect it will be more noisy, though.

That talk of the shroud above reminds me: Is your shroud in good shape? A missing or broken shroud can result in exactly the symptoms you describe.


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## dieselss (Jan 3, 2008)

If the fan hits the bottom of it,,,,its motor motor mounts.


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## fastjohnny (Nov 14, 2002)

How about tweak the fan clutch to engage sooner? Rebend the bimetal spring a little longer IE move the bend as 1/8 toward the end. I've used this with success on my 6.5 diesel.


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## snowcrazy (Nov 18, 2010)

dieselss;1589278 said:


> i have heard that a plow deflector works as well
> not 100% sure but isnt there another fan as well as the clutch??
> can look into a colder thermastat
> assuming you cked the front of the rad, condenser, and everything up front??
> when was the last time you did a total system flush??? like pull off all the hoses and run a garden hose in there??


Ive got a plow deflector in my garage I bought about 2 months ago and installed.. It didnt work....

as for another fan, I added electric fans but they just don't suck hard enough. You can stick your hand in front of the grill and barely feel any air being pulled through. When my clutch fan does in fact come on and you rev motor it sounds like a dump truck its moving so much air. Its just getting it to come on im having trouble with.......

t-stat change wouldnt work. if nothing is cooling the system it just gonna keep rising..

had full system flush last year and all that stuff mentioned above is clean.....

here is something for everyone to think about. just to show that all of this stuff on my truck is working correctly..... my truck got hot on the last snowfall. I had my backpack blower in the back of the truck. I pulled over and blew through the grill and within about 30 seconds my clutch fan came on.............. Water temp fell like a rock and I was on my way. Its the air flow im not having luck with. There is nothing wrong with my clutch fan, it is brand new as of last year replaced with the item number listed here on plowsite. It is the severe/extreme duty clutch fan!


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## snowcrazy (Nov 18, 2010)

theholycow;1589461 said:


> I don't think fuel economy will be affected in any way you can actually notice in your truck with the work it does. I suspect it will be more noisy, though.
> 
> That talk of the shroud above reminds me: Is your shroud in good shape? A missing or broken shroud can result in exactly the symptoms you describe.


No shroud parts missing at all.

Yeah if this were a plow only truck I could care less about the fuel mileage.. It is also my daily driver, also pulls my enclosed trailer daily during mowing season... Id just hate to get 2mpg less every day because i go with this solid mount fan.

I could care less about the noise. I think it sounds good when the fan does engage.... Matter of fact when I have an overheating truck its music to my ears!!! LOL


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## snowcrazy (Nov 18, 2010)

fastjohnny;1589496 said:


> How about tweak the fan clutch to engage sooner? Rebend the bimetal spring a little longer IE move the bend as 1/8 toward the end. I've used this with success on my 6.5 diesel.


I will try anything, and willing to try this....... can you explain how to do it though. Im not following your directions above. can i cut some of the coil off perhaps???


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## theholycow (Nov 29, 2002)

2MPG would be 15%. You're not going to lose 15% of your fuel economy just from the fan. However, you could swap it out for winter/summer.



snowcrazy;1589511 said:


> my truck got hot on the last snowfall. I had my backpack blower in the back of the truck. I pulled over and blew through the grill and within about 30 seconds my clutch fan came on..............


That sounds like a defective clutch (even though it's new), it should come on when it's hot not when you cool it down...unless you're exceeding the temperature that the clutch is made for but I imagine they put plenty of margin into the design.


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## fastjohnny (Nov 14, 2002)

snowcrazy;1589529 said:


> I will try anything, and willing to try this....... can you explain how to do it though. Im not following your directions above. can i cut some of the coil off perhaps???


NO You want it as long as possible. Rebend a little further to the end.


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## RAZOR (Dec 19, 2001)

Is it possible that when you put on the new "extra hd clutch fan" that you got the wrong one? Maybe double check the part numbers. When I installed a plow on my 03 2500hd I had the same problem until I put in the new clutch fan. The truck is getting up there in age, perhaps it time for a new rad?


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## snowcrazy (Nov 18, 2010)

theholycow;1589534 said:


> 2MPG would be 15%. You're not going to lose 15% of your fuel economy just from the fan. However, you could swap it out for winter/summer.
> 
> That sounds like a defective clutch (even though it's new), it should come on when it's hot not when you cool it down...unless you're exceeding the temperature that the clutch is made for but I imagine they put plenty of margin into the design.


I dont think thats what was going on though..... when i blow the air through the grill i think that the air is going through the radiator and finally getting the hot air to the front of the clutch fan....... im not saying that my blower cooled it down..... i only blew through the radiator long enough to get the hot air from the radiator to the front of clutch fan and the fan comes on........ the clutch fan to me works but its not gonna work if the air isnt getting blown through while in transport......


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## theholycow (Nov 29, 2002)

You could suspend a cooking thermometer probe in the vicinity of the fan clutch and see what temperatures look like there. If the clutch is never getting exposed to warm air that might do it, though I thought they engage at least partially based on heat conducted through the shaft.


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## White Gardens (Oct 29, 2008)

I would pull the radiator and do a thorough cleaning.

Heck, they are relatively inexpensive, so replacing it might be the way to go.

Wouldn't be surprised if the fins are clogged up on the upper passenger side section of the radiator.



..............


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## leolkfrm (Mar 11, 2010)

make sure you have a heavy duty clutch on the fan....the corners will be almost square instead of rounded


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## jasonv (Nov 2, 2012)

snowcrazy;1589444 said:


> Thats what Im looking into doing is the locked fan but scared of what that will do to fuel mileage.... I love these trucks for sure but ive known a lot of ppl having trouble with overheating with a plow on the 6.0 chevys......
> 
> Do you think fuel mileage will get hurt having to spin that fan ALL THE TIME instead of a clutch type.. I sure would think so...... Be better than torching a motor is my thinking.


Not only will it hurt fuel mileage, it will murder your power. It takes a LOT of power to run a fan full time. When I was driving an S10 4.3, on a hot summer day the fan would engage fully in slow traffic, and the damned thing couldn't win a race against a smart.

The problem with a fan clutch is that it is trying to generate a balance between the heat coming off the engine via the water pump shaft, and the ambient air passing through the radiator, via the cooling fins. Now your problem is obviously that the air passing the clutch's cooling fins is going the wrong direction through the radiator, so its sucking COLD air from below your truck. The cold air wins out over the hot water.

Here is a little trick for you; insulate the fins on the fan clutch from the cold air. I.e., wrap something around it that will block air flow through it. This will give an advantage to the hot water and let the fan clutch engage. Depending on just how overpowered the hot water is, you may need to also insulate the shaft/hub up to the water pump. You can adjust the insulation on the fan clutch as needed to get the fan running optimally.


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## jasonv (Nov 2, 2012)

theholycow;1589684 said:


> You could suspend a cooking thermometer probe in the vicinity of the fan clutch and see what temperatures look like there. If the clutch is never getting exposed to warm air that might do it, though I thought they engage at least partially based on heat conducted through the shaft.


It is a battle between cold air and hot water. Whichever one wins determines whether or not the clutch engages.


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## jasonv (Nov 2, 2012)

theholycow;1589534 said:


> 2MPG would be 15%. You're not going to lose 15% of your fuel economy just from the fan. However, you could swap it out for winter/summer.
> 
> That sounds like a defective clutch (even though it's new), it should come on when it's hot not when you cool it down...unless you're exceeding the temperature that the clutch is made for but I imagine they put plenty of margin into the design.


EASILY 15%. Probably far far worse. If you're spinning the engine fast, it could drain over 100 hp easily.


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## 2COR517 (Oct 23, 2008)

But the 100 hp lost to the fan would be gained in thrust, like an airplane.

Just be sure to check the mags during preflight


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## basher (Nov 13, 2004)

2COR517;1594646 said:


> But the 100 hp lost to the fan would be gained in thrust, like an airplane.
> 
> Just be sure to check the mags during preflight


and turn off your video games.


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## jasonv (Nov 2, 2012)

2COR517;1594646 said:


> But the 100 hp lost to the fan would be gained in thrust, like an airplane.


Blowing down, like a Harrier taking off.


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## theholycow (Nov 29, 2002)

jasonv;1594791 said:


> Blowing down, like a Harrier taking off.


That will reduce rolling resistance in the tires.


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## tooch420 (Dec 17, 2011)

I have a GMC 2500HD, i removed the fan and clutch and installed dual electric fans with thermosat and separate relay. It has an adjustment for when to kick it on too, As long as you get the correct CFM flow (mines about 6500cfm) for your engine it will be fine. Had it installed for few years now with plow, never goes above 195


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## jasonv (Nov 2, 2012)

theholycow;1594803 said:


> That will reduce rolling resistance in the tires.


Also compensate for the weight of the plow.


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## leolkfrm (Mar 11, 2010)

run your fingers over the fins...if soft and crumbly..time for a new radiator as the heat is not exchanging as it should


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## dfd9 (Aug 18, 2010)

Would it work out to surround the engine with a jacket of liquid nitrogen?

Some helium in the tyres might help as well.


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## 2COR517 (Oct 23, 2008)

I heard helium filled tires saves ball joints


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## maxwellp (Feb 16, 2013)

Check that radiator. Does it look cruddy? Replace it.
Also I have gotten bad NEW fan clutches. Sounds like you have one or both of these problems. 
Or run a Diesel I have to put cardboard in front of the radiator to keep it warm. Ok I know that did not help.


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## dfd9 (Aug 18, 2010)

2COR517;1601019 said:


> I heard helium filled tires saves ball joints


It's really going to kill the downpressure of the front plow, though.


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## 2COR517 (Oct 23, 2008)

Everything is a trade-off in this business


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## basher (Nov 13, 2004)

dfd9;1601187 said:


> It's really going to kill the downpressure of the front plow, though.


Replace the chain with a 2x4 and run the motor backward so you have Down Pressure


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## dfd9 (Aug 18, 2010)

2COR517;1601576 said:


> Everything is a trade-off in this business


True, very true.



basher;1601673 said:


> Replace the chain with a 2x4 and run the motor backward so you have Down Pressure


Good point and excellent idea.


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