Duramax Overheating

djdave33 · February 10, 2008

2005 duramax duelly. I have had it overheat pulling a 3000lb trailer when it was 75 degrees outside. I have had it overheat unloaded and no trailer at 95 degree outside temp. The cooling fan starts to roar and the temp gauge keeps climbing untill the dic starts to flash coolant hot. Took to dealer on several occasions they changed the cooling fan assembly 2 times and then changed out the air cleaner assembly from a 2006 lmn but my truck will still overheat and sound like a SCHOOL BUS. I also have a problem with the steering issues. Namely the hard stiff steering at slow parking lot speeds and or when the truck is stopped and try to turn the steering wheel. It turns ok for about half of the whell travel then it gets so stiff and looses power assist. I have had a new power steering pump installed, new steering gear assembly and was also told on one occasion that one of my tires was a few lbs to low on air that was causing me troubles. Imagine that on a $51000 truck that starting haveing these issues at 1613 miles.. The truck now has 21000 miles on it and I am afraid to use it anymore because I dont want to jeopardize my familys lives driving something that could leave us stranded on the side of the road somewhere. Gm states it can not duplicate some of the problems but the mechanics pull me to the side and say there are a (lot of complaints) about the same problems i am having.

gave20 · February 10, 2008

Almost all LLY's overheat. There are two solutions; one that might work: moving the transmission cooler lower to get more air the the radiator or two, that will work: install a V2 cooling system.

overheating thread found here

and V2 cooling system is found here

djdave33 · March 2, 2008

hi,

Thanks for the reply,

I have been on tc's website and have seen his v2 and other items he has for sale. I am going to try for a gm buyback first, if that dont work I may have to buy his small rad and fan assembly for my truck. I may try to get a rad and shroud fan assembly from a 2006 also... Im just so fed up with the overheating problems.

Bobslob · March 2, 2008

It is a pretty common problem with the LLYs but strangley enough ours has had no problems with 47,000 miles on the odo. Check out the diesel place , the guys over there can answer any question you've got.

Edit: i didnt see the previous links.

djdave33 · March 3, 2008

It is a pretty common problem with the LLYs but strangley enough ours has had no problems with 47,000 miles on the odo. Check out the diesel place , the guys over there can answer any question you've got.
Edit: i didnt see the previous links.

I think your pretty lucky that yours does not overheat. Either that or you dont tow that much.. I dont tow much either and actually I have had mine get hot up steep hills empty when the outside air temps are in the 80's and above.. I have been on deisel place and the deisel page. I Have seen the txchristofer money maker video on his duramax truck overheating. He has a website where he sells a small radiator and a electric fan that fits in front and lower that helps the duramax overheat problem. I have not chosen to go that route I have chosen to try for a buyback under the pa lemon law.

Anyone else have this problem or tried a lemon buyback for an overheating duramax?

thanks

Killerbee · March 3, 2008

Just curious, what state has a lemon law that goes out 3 years?

If your truck overheats empty, it is not LLY related. You may have a defective radiator full of lead. When you are empty, going up a grade:

1. is your fan on?

2. what gauge are you using to define "hot"?

Killerbee · June 16, 2008

Did your problem go away?

I have a simple test for you to do. Tap the turbo out pipe with a boost sensor, and report the boost that you see.

I am suggesting that you have a highly restricted induction tract. This simple test will confirm it. The amount of heat generated by the turbo, under restriction, is enormous, and will heatsoak the CAC, in front of the radiator. Google search "Thermal Feedback".

Shaners · June 16, 2008

What does the temp gauge read?

On a 90+ degree day towing my 4K lb boat with 5 people in the truck and the AC on mine reads about 200-205. Tranny is running 175-180. (I know these aren't very acurate gauges)

These temps are on a hilly 2-lane road.

I have never had an over heat or hot coolant on my DIC.

jpringle3 · June 17, 2008

He is saying he has an LMM in a 2006, must be real special kind of guy, I have a 2007 NBS and I pulled a 7000lb trailor and had the box full of wood and the hill is about 3500 FT elivation change and it has a 40 mph corner at the bottom of one section then an eight degree section that i pulled at 55 MPH. No problems, what I did see was the trans temp went up first off as if the cooler was not open then it went right down. First thing he should do is know at least what he has, smells to me like he has a Nissan Hard body.