Our 2005 GMC Sierra Diesel Dually (with two years left on the extended warranty) is starting to overheat on steep upgrades. It's not done this before and if I gear down and keep the RPM's between 2,000 and 2500 it's still sending temerature warnings on our Banks electronic engine braking system. This is new to us. Headed all the way to TN from Carlsbad, NM but dreams of Howard and Linda's engine are disturbing me. Fluid levels good. Had fuel injector. Pump and two injectors replaced last fall. Cooled it down and added water today.
I had to slow to about 25 MPH up a steep grade today, very unusual.
Thoughts and suggestions?
Sherry
Alie and Jims Carrilite said
07:00 PM Apr 9, 2014
Set the Banks to the stock level. If it can read the EGT temps monitor those as well. Chances are your over fueling and it increases the exhaust temp which will heat the engine. If your not running a Tuner, but just the engine brake, check for a hose that is collapsing when it gets hot. Check between your radiator for trash and a build up of bugs that may be blocking air flow. Is your cooling fan coming on? I've seen very few D-max engines have heat issues.
MarkS said
09:49 PM Apr 9, 2014
Where did you find a big hill between NM and TN?
Is it only overheating when you are working it? Do you have a coolant leak? Does your coolant cap seal well? Is it actually overheating or are you just getting high temp alarms?
WestWardHo said
10:12 PM Apr 9, 2014
Good questions Mark. From Deming to Carlsbad at the moment some long gradual uphill grades, guessing 4%-5% or so. Getting high temp alarms but engine temp gage showing near max also. Coolant cap is tight. We've seen no indication of a coolant leak.
Jim going to check your suggestions tomorrow.
Thanks,
Sherry
Lonney Wade said
12:18 AM Apr 10, 2014
Sherry, let me take a whack at this.
An overheating engine can be a few things, first check with looking at the oil dipstick, does it look like or smell like it has coolant or antifreeze on the dipstick which means a blown head gasket or could be a EGR cooler leaking and a lot of white steam coming out of your tailpipe. Your thermostat could be sticking or faulty. Your entire coolant system may need to be flushed. Also look at your dash to see if your tranny temperature is running warmer than normal, should be under 220%. Water pump could be failing. Radiator fan clutch could be failing Hops this helps.
Lonney
PIEERE said
06:59 AM Apr 10, 2014
Without looking at it; I would say a fan clutch problem!!! Check you serpentine belt also for weather cracks and glazing. PIEERE
Lucky Mike said
07:05 AM Apr 10, 2014
Start with Allie & Jims Recommendation first....then stop and have it checked......it sounds just like Jim said if its happening on the down hill that you are over fueling.......also check your trailer brakes to make sure they are set correctly and your not putting all the braking on the truck.
Jim and Linda said
07:31 AM Apr 10, 2014
Unfortunately, I've replaced a lot of blown head gaskets on 2005 Duramax engines for this same type of concern. If it's losing coolant with no visible leaks, it's most likely going into one of the cylinders from the bad head gasket.Hope your problem is not that serious, but just wanted to let you know what I’ve seen over the years.Good luck!
Jim
The Bear II said
08:01 AM Apr 10, 2014
Each time I've had a cooling problem on hills it's been due to bad fan clutch (twice) or thermostats (also twice).
There is a product that may help as a temporary solution it's by Royal Purple you can get it at most auto supply locations. It's called "Wetter Water". It lowered my temp by 20 degrees on hills.
Bill and Linda said
08:46 AM Apr 10, 2014
Sounds like the thermostat in the fan is going bad or is bad.When engine temps go up a ibt this sensor “locks up” the fan to direct drive and provides additional cooling when required.Other times it is free turning.That’s the first thing I would check if you haven’t had this problem before.
Also make sure you are in tow-haul. An easy thing to forgetIt changes the gearing shift points among other things which can impact cooling. It's also important to keep transmission temps proper. This is true for all trucks, Chevy, Ford or Dodge.
Jim and Linda said
10:11 AM Apr 10, 2014
Wanted to add that there is a way to tell if the head gasket(s) are likely the problem. With the engine completely cool (usually after sitting overnight) and the coolant level full, squeeze the upper radiator hose and it should be squishy. Start the engine and if the upper hose becomes firm in just a few minutes, there's combustion gases entering the cooling system. You can also let the engine idle with the coolant reservoir cap off and watch for coolant to be pushed out of the container even on a cold engine. You may also observe bubbles coming up into the coolant reservoir.
If you have a power booster on your truck, it does add power, but it also places extra stress on the head gaskets and other engine components.
For anyone interested, here's what to expect if you have to replace your head gaskets. I like to remove the cab from the chassis for easy access to the engine. You can see the blown out gasket and minor damage to the cylinder head surface.
-- Edited by Jim and Linda on Thursday 10th of April 2014 10:12:40 AM
Lonney Wade said
12:02 PM Apr 10, 2014
Jim, I like your pictures brings back old memories. Question for ya, since you had the motor down to that point did you rebuild the lower end, bearings, oil pump, Rings or if that was ok did you have to resurface the heads, if they were good just redo the heads and change the head gaskets. I used to rebuild top fuel blower sand drag engines when I was younger, do the lower end one day and the top end the next day, I really did enjoy doing that because, one thing the motor was clean from the start, you know what I mean if you have been working on engines..... LOL !!!
Lonney
Jim and Linda said
12:50 PM Apr 10, 2014
This was just replacing the head gaskets. It wasn't necessary to do anything with the lower end. I have to say these Duramax engines are pretty bulletproof when it comes to the lower end! It wasn't necessary to do anything with the heads either. Typically, with this type of failure, the heads are not warped and the little bit of scoring on the combustion chamber surface where the gasket breakage occurs is so minor there's no reason to replace the head. (If these heads get warped more than 0.004" they have to be replaced.) Put the new gaskets on, re-use the heads, Install NEW head bolts and put it all back together.
I never did any tinkering around with the cool high performance stuff you worked on! That sounds awesome! I did have a few Hot Rod cars when I was younger though. Fun, fun!
WestWardHo said
10:15 AM Apr 11, 2014
Wow, complicated pictures there, glad we didn't have to do that. After visiting the Carlsbad Caverns - awesome of course - we took it to a Chevy dealer in town. They showed us Service Bulletin #06-06-04-036D. "Engine overheats when towing or hauling on long inclines". Checked everything on it and then changed the air filter! Good to go, running 10 degrees cooler on level ground today.
Yes, I had it in tow. Posted above in case anyone else has this issue and thank you all for your help!
Service advisor said mechanic said the truck looked very well maintained, that felt good!
Sherry
BiggarView said
10:20 AM Apr 11, 2014
Glad it was something simple.
Lucky Mike said
10:44 AM Apr 11, 2014
Like....... Like ........And a H a Pp Y Dance for you that it was not a major malfunction!!!..........may your journey be alot less stressful the rest of the way !!!
-- Edited by Lucky Mike on Friday 11th of April 2014 10:45:48 AM
TRAILERKING said
10:53 AM Apr 11, 2014
Hard to believe it was just an "Air Filter" issue.
plhaw said
11:24 PM Apr 11, 2014
Sherry,
I am almost positive that we have the same engine as you do, 2005 duramax "LLY". You can check the engine version by the VIN number (one particular digit in the VIN I think) and then look it up on the internet. If you go to dieselplace.com, second generation LLY engines, you will see a sticky post for "engine overheating". In summary, this particular engine has a couple of design flaws that can be fixed by a home mechanic such as yourself! The weak link in the chain is the air inlet into the turbo. The turbo air inlet is too small and limits the air into the engine. This was corrected in the next version of the engine, LBZ. With a little elbow grease, the LBZ turbo air inlet can be installed on your engine to increase power and prevent overheating.
The LLY engine also has an issue with getting cold air to the air filter at slow towing speeds. There are tons of different ways to get cold air to your air filter box. I think dieselplace.com has some posts on that too.
I have made the corrections to our truck and don't have any overheating issues at all anymore.
Hope that helps,
Phil
Jim and Linda said
07:19 AM Apr 12, 2014
Sherry,
So glad to hear it was something simple! You must be very relieved.
Thanks for letting us know what corrected the problem!
MarkS said
11:42 AM Apr 12, 2014
Sherry, I knew you could fix it. When I first got mine I would get indications that the oil was overheating. Every technician on the planet, and I do mean every single one, scratched their head. One day while climbing up to Flagstaff on 40 I pulled over as the engine overheated. I was boiling water but my gauge indicated 160 degrees. I thought, wait a minute, water doesn't boil at 160 degrees. I nursed it to Albuquerque where I discussed the situation with a tech. Since my temp gauge was supposed to be at 180 we decided to change the water temp sensor. Bingo. Problem solved. Since the sensor was reporting low water temps the water was getting too hot and since the oil is cooled by the water it was getting too hot also. Once the water sensor was changed the fan started working correctly and everything was good in the village. After spending well over $1000 on parts I didn't need, we found the problem in a $30 sensor that took less than 5 minutes to change.
Lonney Wade said
12:00 PM Apr 12, 2014
Thank you mark, I will put that in the (things to know book), If you have more I"m listening, you can never be too old and never have too much information.
Lonney
VanMar said
04:55 PM Apr 12, 2014
WestWardHo wrote:
Checked everything on it and then changed the air filter! Good to go, running 10 degrees cooler on level ground today.
Sherry,
I'm glad it was something simple but I just gotta chime in with this: whenever someone gets their vehicle serviced, every service center that I'm aware of will tout their "free 27 point vehicle check". It's their way of increasing the bottom line. Anecdote: our car was just in for a recall. Wife was given a 'report' that said we needed 1) throttle body cleaned 2) cabin air filter replaced, and 3) nitrogen in our tires (we've discussed that!). All that for only $349!
My point is this--the air filter is the easiest thing to check, replace, and make a quick $30 or so. If the air filter was so clogged as to make the engine overheat, the last place to service your vehicle fell sadly down on the job. I guess if you got it serviced at the same place every time, you could do something about it. Being full timers, you no doubt get the truck serviced someplace different every time.
Sherry, you may just have to roll up your sleeves, get under the hood, and check things out yourself! :)
Glad you're running cool.
WestWardHo said
08:27 AM Apr 13, 2014
Oh nooooo, I'll never roll up my sleeves and get under the hood except to check fluid levels, anything beyond that is beyond me! Good points here. When we left Fort Stockton to San Antonio yesterday we noticed at a low ambient temperature (70) AT FIRST 30 minutes or so up very gradual inclines the engine temp was starting to climb. (225 degrees) Cooled down immediately when level or down hill. After 30 minutes or so it didn't do that anymore but we're suspecting there is something more. You're right about different mechanics, Vance. Going to check/replace thermostat and check that turbo air inlet thingie. We've towed with this truck up and down huge grades traveling to Oregon thru California from Arizona and back again.
But as we set up yesterday Jesse noticed we have a leak in one to the Trilogy wheel bearing seals. They were repacked in January when we had one bad (different) seal then (same side of the rig). So now we need to find someplace to get that fixed here in San Antonio. Any suggestions?
Let's see, since **I** started driving a week ago we've had one tire stem leak, engine overheating and now this seal. Hummmmm.....
Sherry
On edit: emails sent to both Lippert CSR and Trilogy manager of customer service to be in their inboxes in the AM.
Evidently know issue with Lippert axles but past customer service with Lippert has been outstanding. We'll see.
got a good recommendation from a couple of guys in the office for repair.
-- Edited by WestWardHo on Sunday 13th of April 2014 09:47:21 AM
-- Edited by WestWardHo on Sunday 13th of April 2014 09:49:03 AM
The Bear II said
10:55 AM Apr 15, 2014
It's funny how you'll go for months or even a year or two without a problem and then all of the sudden it will be several problems in a row or all at the sametime.
About 10 years ago it seemed like everytime we moved it was another $500 to $1500 worth of repairs. That lasted for several months and then we had about 5 years of no problems.
Last year we had a couple of issues pop up so now we are hoping for several good years...knock on wood.
WestWardHo said
06:29 AM Apr 22, 2014
Bear II,
It is funny how things seem to pop up in sequence and then settle down for a while. Ours hasn't decided to do that yet.
We had ordered 17.5" wheels and tires based upon recommendations from wonderful experienced friends for increased safety. The arrived Friday and we had hired a mobile RV service company to come install them yesterday. Super nice tech came out and first removed tire with leaking seal and immediately noticed the springs were shot on both 8,000 lb axles on both sides of the rig. This was causing wheels to overheat and therefore the seal leaks. I had been in contact w/Lippert for well over a week about seal leak and they were basically denying any responsibility.....until tech got pictures and I fired off a "hot" email to a Lippert supervisor. Per Tech, the springs were too light for axles and rig and currently unsafe to drive. Lippert immediately called Jesse and asked for pictures and promised to overnight replacement parts to go out today and arrive Wednesday. Lippert also said we have 8,000 springs. Hope it all makes it because our current park managed to extend us for one day but they're full up starting Thursday so we have to be out by noon.
MorRyde here we come (after the Rally IF we make the Rally). Really, really, really understand what Jack Mayer, Bill & Linda and Howard others say about the foundation of a rig being so important!
Besides dealing long distance with home loan and the VA and feeling overwhelmed by all the paperwork & issues we have had a great time touring the Austin area with Jesse's sister.
Sherry
Den-Bev said
08:23 PM May 2, 2014
My GMC has overheated from when I bought it new GMC put the 06 air box in it did not fix it I bought the Aux Rad but not installed it yet.
Our 2005 GMC Sierra Diesel Dually (with two years left on the extended warranty) is starting to overheat on steep upgrades. It's not done this before and if I gear down and keep the RPM's between 2,000 and 2500 it's still sending temerature warnings on our Banks electronic engine braking system. This is new to us. Headed all the way to TN from Carlsbad, NM but dreams of Howard and Linda's engine are disturbing me. Fluid levels good. Had fuel injector. Pump and two injectors replaced last fall. Cooled it down and added water today.
I had to slow to about 25 MPH up a steep grade today, very unusual.
Thoughts and suggestions?
Sherry
Is it only overheating when you are working it? Do you have a coolant leak? Does your coolant cap seal well? Is it actually overheating or are you just getting high temp alarms?
Jim going to check your suggestions tomorrow.
Thanks,
Sherry
Sherry, let me take a whack at this.
An overheating engine can be a few things, first check with looking at the oil dipstick, does it look like or smell like it has coolant or antifreeze on the dipstick which means a blown head gasket or could be a EGR cooler leaking and a lot of white steam coming out of your tailpipe.
Your thermostat could be sticking or faulty.
Your entire coolant system may need to be flushed.
Also look at your dash to see if your tranny temperature is running warmer than normal, should be under 220%.
Water pump could be failing.
Radiator fan clutch could be failing
Hops this helps.
Lonney
Unfortunately, I've replaced a lot of blown head gaskets on 2005 Duramax engines for this same type of concern. If it's losing coolant with no visible leaks, it's most likely going into one of the cylinders from the bad head gasket. Hope your problem is not that serious, but just wanted to let you know what I’ve seen over the years. Good luck!
Jim
There is a product that may help as a temporary solution it's by Royal Purple you can get it at most auto supply locations. It's called "Wetter Water". It lowered my temp by 20 degrees on hills.
Sounds like the thermostat in the fan is going bad or is bad. When engine temps go up a ibt this sensor “locks up” the fan to direct drive and provides additional cooling when required. Other times it is free turning. That’s the first thing I would check if you haven’t had this problem before.
Also make sure you are in tow-haul. An easy thing to forget It changes the gearing shift points among other things which can impact cooling. It's also important to keep transmission temps proper. This is true for all trucks, Chevy, Ford or Dodge.
Wanted to add that there is a way to tell if the head gasket(s) are likely the problem. With the engine completely cool (usually after sitting overnight) and the coolant level full, squeeze the upper radiator hose and it should be squishy. Start the engine and if the upper hose becomes firm in just a few minutes, there's combustion gases entering the cooling system. You can also let the engine idle with the coolant reservoir cap off and watch for coolant to be pushed out of the container even on a cold engine. You may also observe bubbles coming up into the coolant reservoir.
If you have a power booster on your truck, it does add power, but it also places extra stress on the head gaskets and other engine components.
For anyone interested, here's what to expect if you have to replace your head gaskets. I like to remove the cab from the chassis for easy access to the engine. You can see the blown out gasket and minor damage to the cylinder head surface.
-- Edited by Jim and Linda on Thursday 10th of April 2014 10:12:40 AM
Jim, I like your pictures brings back old memories.
Question for ya, since you had the motor down to that point did you rebuild the lower end, bearings, oil pump, Rings or if that was ok did you have to resurface the heads, if they were good just redo the heads and change the head gaskets.
I used to rebuild top fuel blower sand drag engines when I was younger, do the lower end one day and the top end the next day, I really did enjoy doing that because, one thing the motor was clean from the start, you know what I mean if you have been working on engines..... LOL !!!
Lonney
I never did any tinkering around with the cool high performance stuff you worked on! That sounds awesome! I did have a few Hot Rod cars when I was younger though. Fun, fun!
Yes, I had it in tow. Posted above in case anyone else has this issue and thank you all for your help!
Service advisor said mechanic said the truck looked very well maintained, that felt good!
Sherry
Glad it was something simple.
Like.......
Like 
........And a H a Pp Y Dance for you that it was not a major malfunction!!!..........may your journey be alot less stressful the rest of the way !!!
-- Edited by Lucky Mike on Friday 11th of April 2014 10:45:48 AM
Hard to believe it was just an "Air Filter" issue.
I am almost positive that we have the same engine as you do, 2005 duramax "LLY". You can check the engine version by the VIN number (one particular digit in the VIN I think) and then look it up on the internet. If you go to dieselplace.com, second generation LLY engines, you will see a sticky post for "engine overheating". In summary, this particular engine has a couple of design flaws that can be fixed by a home mechanic such as yourself! The weak link in the chain is the air inlet into the turbo. The turbo air inlet is too small and limits the air into the engine. This was corrected in the next version of the engine, LBZ. With a little elbow grease, the LBZ turbo air inlet can be installed on your engine to increase power and prevent overheating.
The LLY engine also has an issue with getting cold air to the air filter at slow towing speeds. There are tons of different ways to get cold air to your air filter box. I think dieselplace.com has some posts on that too.
I have made the corrections to our truck and don't have any overheating issues at all anymore.
Hope that helps,
Phil
So glad to hear it was something simple! You must be very relieved.
Thanks for letting us know what corrected the problem!
Thank you mark, I will put that in the (things to know book), If you have more I"m listening, you can never be too old and never have too much information.
Lonney
Sherry,
I'm glad it was something simple but I just gotta chime in with this: whenever someone gets their vehicle serviced, every service center that I'm aware of will tout their "free 27 point vehicle check". It's their way of increasing the bottom line. Anecdote: our car was just in for a recall. Wife was given a 'report' that said we needed 1) throttle body cleaned 2) cabin air filter replaced, and 3) nitrogen in our tires (we've discussed that!). All that for only $349!
My point is this--the air filter is the easiest thing to check, replace, and make a quick $30 or so. If the air filter was so clogged as to make the engine overheat, the last place to service your vehicle fell sadly down on the job. I guess if you got it serviced at the same place every time, you could do something about it. Being full timers, you no doubt get the truck serviced someplace different every time.
Sherry, you may just have to roll up your sleeves, get under the hood, and check things out yourself! :)
Glad you're running cool.
Oh nooooo, I'll never roll up my sleeves and get under the hood except to check fluid levels, anything beyond that is beyond me! Good points here. When we left Fort Stockton to San Antonio yesterday we noticed at a low ambient temperature (70) AT FIRST 30 minutes or so up very gradual inclines the engine temp was starting to climb. (225 degrees) Cooled down immediately when level or down hill. After 30 minutes or so it didn't do that anymore but we're suspecting there is something more. You're right about different mechanics, Vance. Going to check/replace thermostat and check that turbo air inlet thingie. We've towed with this truck up and down huge grades traveling to Oregon thru California from Arizona and back again.
But as we set up yesterday Jesse noticed we have a leak in one to the Trilogy wheel bearing seals. They were repacked in January when we had one bad (different) seal then (same side of the rig). So now we need to find someplace to get that fixed here in San Antonio. Any suggestions?
Let's see, since **I** started driving a week ago we've had one tire stem leak, engine overheating and now this seal. Hummmmm.....
Sherry
On edit: emails sent to both Lippert CSR and Trilogy manager of customer service to be in their inboxes in the AM.
Evidently know issue with Lippert axles but past customer service with Lippert has been outstanding. We'll see.
got a good recommendation from a couple of guys in the office for repair.
-- Edited by WestWardHo on Sunday 13th of April 2014 09:47:21 AM
-- Edited by WestWardHo on Sunday 13th of April 2014 09:49:03 AM
About 10 years ago it seemed like everytime we moved it was another $500 to $1500 worth of repairs. That lasted for several months and then we had about 5 years of no problems.
Last year we had a couple of issues pop up so now we are hoping for several good years...knock on wood.
It is funny how things seem to pop up in sequence and then settle down for a while. Ours hasn't decided to do that yet.
We had ordered 17.5" wheels and tires based upon recommendations from wonderful experienced friends for increased safety. The arrived Friday and we had hired a mobile RV service company to come install them yesterday. Super nice tech came out and first removed tire with leaking seal and immediately noticed the springs were shot on both 8,000 lb axles on both sides of the rig. This was causing wheels to overheat and therefore the seal leaks. I had been in contact w/Lippert for well over a week about seal leak and they were basically denying any responsibility.....until tech got pictures and I fired off a "hot" email to a Lippert supervisor. Per Tech, the springs were too light for axles and rig and currently unsafe to drive. Lippert immediately called Jesse and asked for pictures and promised to overnight replacement parts to go out today and arrive Wednesday. Lippert also said we have 8,000 springs. Hope it all makes it because our current park managed to extend us for one day but they're full up starting Thursday so we have to be out by noon.
MorRyde here we come (after the Rally IF we make the Rally). Really, really, really understand what Jack Mayer, Bill & Linda and Howard others say about the foundation of a rig being so important!
Besides dealing long distance with home loan and the VA and feeling overwhelmed by all the paperwork & issues we have had a great time touring the Austin area with Jesse's sister.
Sherry