Coolant Temp

[hackengineering]

I have had a 2010 with Auto completely stock with 60,000miles for about 6 months now and noticed large fluctuations on the coolant temp when towing. This is my forth Cummins and i have never had one heat up past 205 while towing even here in the high country i live in. I know this truck has a warmer thermostat than the past trucks but i am surprised how much it varies in temp. A few weeks back i towed my 10K trailer against the wind and it would heat up to about 220 and then the fan clutch would kick in but it would do this fairly often. I was not really towing that hard and even tried to shift down to 5th to see if more RPM would help. This truck seems like each time i hit a hill it will climb in temp about 10deg. It just seems odd given my 06 and 00 never would get warm and they were chipped with quite a bit more HP. I have a new thermostat coming that is a cummins brand but are you guys seeing these kind of fluctuations on a stock truck. Coolant level is fine, does not raise in reservoir. I am headed to Moab in a few weeks and would like to have this resolved.

Thanks for the help

CH

 

[RustyJC]

According to the EVIC, the fan doesn't kick in until 219 degrees F. Once it kicks in, temps drop quickly back to ~200 degrees F at which point the fan shuts off. Towing our 16,000 lb 5th wheel, coolant temps (again, on the EVIC) will stay around 203 to 205 degrees F on the flat and level, but long grades will drive it up to the fan engagement point. I've never seen it over 219 degrees F, even towing in the Davis Mountains in West Texas on a 105 degree day.



Rusty

 

[Gonzo 1066]

I think what you are seeing is normal for the newer trucks. Cummins wants these engines to run warmer than they used to. The cooling system is HUGE compared to the previous gen trucks.

 

[Hoefler]

Heading north out of town where we live, is a 2. 5 mile stretch that starts out at a 6% grade and finishes out at the to at a 8% grade, towing our 40' fifth wheel, I have seen 229* on the EVIC since it was new. Like said above, the fan does not engage until the 220* mark, and has always cooled down very quickly. Never thought twice about it.

 

[jkern]

Yep, sounds about normal. mine does the same thing as everyone else described within a degree or two. I think they like to run these trucks warmer in the name of emissions.

 

[hackengineering]

Yep, sounds about normal. mine does the same thing as everyone else described within a degree or two. I think they like to run these trucks warmer in the name of emissions.

Thanks for all the replies. Good to hear its not just this truck. I live at 8500ft here in Colorado so before I start some longer pulls I wanted make sure that was normal. There quite a few things these 6. 7's do that will need to get used to.

Ch

 

[MChrist]

I think your truck has a fever... and the only prescription is... MORE COWBELL!!

(not everyone will get that. . but I know you will)

 

[mwilson]

I think your truck has a fever... and the only prescription is... MORE COWBELL!!



(not everyone will get that. . but I know you will)

I got it... good avatar!!!!

Mike.

 

[hackengineering]

MORE COWBELL is about the only cure for most things i build that's for sure.

 

[RVTRKN]

:-laf:-laf:-laf:-laf I have Blue Oyster Cult on my iPhone, and every time I listen to them I remember that.