Are some Duramax trucks overheating?

[Corwin]

Lots of discussion on the 2004.5 and 05 overheating on the the other big diesel forum site, but not talked about here at all.

Is it really an issue at all on them?

[Sheldon Kuhn]

First I have ever heard of that one. My 04.5 engine temp is rock solid whether pulling or not. The tranny temp cycles slightly but no where near hot.

What is it they say the problem is? Engine or tranny?

[JD Diesel]

Same hear mine ran pretty close to normal at 21980 pds up hill down hill and all around. JD ;)

[madmatt]

I've only seen one that was actually overheating. It did it while driving around w/ a snowplow on the front. A new fan clutch took care of it. I have seen blown head gaskets and leaking injector cups push compression gases into the cooling system and cause coolant to blow out the overflow and has been mistaken as running hot by some.

[Corwin]

I hope the blown head gaskets and leaking injector cups are rare, as me want to jump off the fence and get a diesel truck and most likely be a Chev.

Like the ford also but think to many issues with the 6.0 that I have read about.

[madmatt]

Yeah those problems are very, very few and even farther between. I'd say 75-80% of the trucks I work on other then maintence, are just in need of a fuel filter.

[Kennedy]

I've seen what I'd consider higher than desireable ECT on hills at elevation, but no overheating.

[iljusin]

Pulling heavy load and with RPMs over 2,600 I saw temperature increase.

[kriskaza]

I have a 04.5 LLY dually pulling 13,000# gooseneck trailer. On 6% grades the water temp is reaching 240', the command center reports hot coolent and the trany temp reaches at least 230'. I turn off the A/C and the temp stops going up. This has happened three times now at outside temps of 80' - 100'. Took it to the dealer to check out the coolent systems. Dealer says it's fine. Seems wrong to me. This truck should be able to pull that load over a 6% grade without overheating. Anybody else having this problem? Anybody have any suggestions. Does a 4" cat/back exhaust system help? Any suggestions/comments would be appreciated.

[Kennedy]

Originally posted by kriskaza:
I have a 04.5 LLY dually pulling 13,000# gooseneck trailer. On 6% grades the water temp is reaching 240', the command center reports hot coolent and the trany temp reaches at least 230'. I turn off the A/C and the temp stops going up. This has happened three times now at outside temps of 80' - 100'. Took it to the dealer to check out the coolent systems. Dealer says it's fine. Seems wrong to me. This truck should be able to pull that load over a 6% grade without overheating. Anybody else having this problem? Anybody have any suggestions. Does a 4" cat/back exhaust system help? Any suggestions/comments would be appreciated. Do you hear the fan clutch come in? I have full free flow exhaust and it gets warm, but 220-230 is max.

[DmaxMaverick]

Just thinking out loud here. I don't have heat issues (other than the 105

[Oilbrnr]

Mine has overheated twice now. Both times at 4-5000' pulling 10k here in AZ. (Outside temps less than 90*).

I'm one of the ones on the other board trying to figure this situation out. Just thought I'd check in over here and see if anyone else has had issues. Looks like there are some cases. GM is of no help yet.

Discouraging.

[D-max Man]

I have done a little digging around on this issue and this is what I have been told:

"There is an issue with some new Duramax equipped trucks running hot, however it is not an issue with the engine. The issue appears to be with the cooling system design on the truck side".

If it is an air flow issue it seems like the GMC would have an advantage.

[VANBC2500HDDA]

My truck seems to kick the fan in at the start of a drive if you work it hard right away... like leaving a campground and hitting the highway at the bottom of a big hill... this to me would seem that maybe the thermostat is set to something very close to the clutch fan initiate speed.

Like thermostat set to 195 and clutch engage at 200... so by the time the thermostat opens up, it has a bit of a runaway temperature problem...

I dont know much about diesel engines, but if the operating temp sweet spot is 195 them maybe the clutch engage should be a bit higher... otherwise if its just an emissions thing... dropping in a colder thermostat might be the way to go.