2011 4500 Overheating in 4th

[MisterBean]

Not sure what is "normal", but during my trip from Albuquerque, NM to San Antonio, TX round-trip, empty, I was running pretty consistently 203-212 degrees the whole trip. The 203-208 was across the flats (only small hills) and the temp was 98 degrees outside. The 212 was down on I-10, just east of Fort Stockton, and the temp was 107 outside, so??? Well, that appears to be "my normal", and I haven't found anything outside of those numbers around town, either...

 

[AH64ID]

Not sure what is "normal", but during my trip from Albuquerque, NM to San Antonio, TX round-trip, empty, I was running pretty consistently 203-212 degrees the whole trip. The 203-208 was across the flats (only small hills) and the temp was 98 degrees outside. The 212 was down on I-10, just east of Fort Stockton, and the temp was 107 outside, so??? Well, that appears to be "my normal", and I haven't found anything outside of those numbers around town, either...

The 10-11 trucks use a hotter thermostat than the 03-09 trucks, so your normal is normal for a 10+.

 

[HBarlow]

Is the hotter running temps mandated to meet another bs epa requirement? Seems like that would reduce service life expectancy.

 

[AH64ID]

The MY07. 5 6. 7 met 2010 emissions so I doubt it's for the EPA, my guess is that along with the smaller intercooler in MY08 it improves the fuel economy by reducing regen requirements.

 

[rashwor]

I don't think this is your issue since your truck is a new '11, but I have seen when a water pump is worn out (impeller severly worn) that higher engine rpms would cause higher coolant temps because basically, at higher engine speeds you would have water pump cavitation and resulting reduced water flow.



Your issue is backwards to what I would expect. I would expect it to run cooler in lower gears with higher rpms. Mine works this way, but I have never towed with that kind weight and I am out of my 5. 9 sandbox. :-laf

 

[AH64ID]

I was wondering if maybe the trans is the culprit? Excessive slippage in 4th and super heating the radiator? I have seen hot trannies overheat motors before... thou generally on older radiators.

 

[PLefever]

transmission temp stays steady, never moves a blip. Disconnected the EGR this weekend and ran about 250 miles empty. Truck ran GREAT, much quicker in the lower gears and pulled down 2mpg better. The test came yesterday with a 103 ambient temp, and 21k trailer so total gvw of right at 31k 20mph wind from the side and head. Ran the truck much harder than I usually drive it, letting it roll off on hills to 30 (without cars behind me anyway) and then pounded on it, highest the temp got was 215!!! not even hot enough to start the fan up. I need to run a few more days hard to confirm but today I am of the opinion that the EGR is with out a doubt the culprit.

 

[HBarlow]

That's interesting. The EGR may be a much bigger detriment than I realized.

 

[PLefever]

I would imagine that since the butterfly valve is still closing while the computer tells it to dump egr that when that valve is disabled and there is unrestricted cooler air going into the cylinders it may drop a bit more. Now for that potatoe stuck in the exhaust pipe... hmmm

 

[AH64ID]

That's interesting. The EGR may be a much bigger detriment than I realized.

I would guess there is something wrong with the EGR in this case.

I would imagine that since the butterfly valve is still closing while the computer tells it to dump egr that when that valve is disabled and there is unrestricted cooler air going into the cylinders it may drop a bit more. Now for that potatoe stuck in the exhaust pipe... hmmm

I think the biggest effect of the EGR on the coolant temp is the cooler.

 

[PLefever]

True, however at this point the egr is simply unplugged so all systems (i think) would be believing to be operable its just not letting the air into the cylinder head?, the intake butterfly will modulate while doing this?, something in the cab and chassis software is telling it to dump high amounts of egr under high boost loads, not sure how to fix that other than a full delete kit or dodge deciding they fubared the software. At this point the dealer is clueless, so if it continues to pull with low temps this way, H&S will be the next call and somemore parts may fall off by accident.

 

[AH64ID]

There is a good change the EGR valve is bad, otherwise there would be more people with overheat issues.

When you unplug the EGR it closes the valve, the ECM thinks the valve is bad and throw's a code, and doesn't try to use it. . luckily without a limp mode. There should be no modulation while unplugged.

My guess is the something in the valve is dumping more EGR than needed in your 4th gear accelerations. This effects coolant in 2 ways, one is the EGR cooler is working overtime and the added temp to the intake air raises the temp of the intake air in the head, and the head is where most of the heat into the coolant comes from.

 

[PLefever]

I think that your spot on with what I have been thinking, the only problem is dodge won't do squat without a code, could be a failure in the servo motor section at the end of the cooler, could be software, either way, I need to pull a load with this truck and will look for the quickest solution. I did however assume that even though it was unplugged that the computer would still continue to dry fire so to speak, hadn't considered that it might just make that system disfunctional. I am not seeing the downside to a delete though, gonna a give it a few more days and take it to the dealer and report my experiment (they already know about it, just couldn't/wouldn't do it on their own) and give them a chance to see if it can be rectified.



Perry

 

[PLefever]

There have been 174 overheat complaints in this region (what ever that is), none quite as hot as mine, but I do pull heavy



p

 

[AH64ID]

Interesting, all on the C&C trucks?

If the ECM were to try to "dry fire" the EGR it would probably effect the timing, duration, etc and that wouldn't be good if it was 100% outside air.

The only issue with deletes is your warranty is gone for the most part, but then again 99% of warranty issues are with the emissions junk!

 

[HBarlow]

Interesting, all on the C&C trucks?

If the ECM were to try to "dry fire" the EGR it would probably effect the timing, duration, etc and that wouldn't be good if it was 100% outside air.

The only issue with deletes is your warranty is gone for the most part, but then again 99% of warranty issues are with the emissions junk!

I never thought of the warranty issue that way. You're absolutely right. If we didn't have the sorry emissions control crap on our engines in the first place we would have no worries about a warranty.

 

[PLefever]

I don't know if those heat issues are on just C&C, it was printed on the startech sheet that said condition normal. .

good point on the warranty, although I'm with Harvey, I have some other ctd that are pushing 300k and don't even think about them, so not too concerned with the basic engine without the emission eq, just a shame a guy has to mess with them to make them run as designed. thats the reason I got rid of my god awful F450 (dealer still has it, 10mo later) a person has to consider inspections and what have you, but don't plan on going to CA any time or ever, might slit the exhaust pull the goodies and tig back together and leave it on the truck.



p

 

[EB]

Other than the time I had a cracked egr cooler (that pushed all the coolant out) my truck has never run hot. I pull heavy in the heat every day and will usually run just a little over the 200 mark. On some of the larger hills it will get higher but if it ever makes it up to where the fan has to kick in it comes right back down. My fan very seldom locks in. Of course there have been several things fall off my engine along the way. That might be helping some.

 

[HBarlow]

EB,

True but you didn't have any heating issues before some of the junk fell off, right?

 

[EB]

EB,



True but you didn't have any heating issues before some of the junk fell off, right?

No, my truck has never run hot. I can probably count the number of times it has gotten hot enough to lock up the fan on one hand. With a load it runs about one needle width above 200.