High Temps 2011 Yukon XL Denali

[Klewis]

What is best way to lower engine temp while driving or towing in hot Arizona conditions? Should I install a bigger transmission cooler in place of stock cooler? I’m trying to avoid hitting 235 degrees while towing. Any advice?

 

[swathdiver]

What is best way to lower engine temp while driving or towing in hot Arizona conditions? Should I install a bigger transmission cooler in place of stock cooler? I’m trying to avoid hitting 235 degrees while towing. Any advice?

Welcome to the forum Kirk. See post #290 in this thread: https://www.tahoeyukonforum.com/threads/useless-information.97483/page-29

Is 235 the coolant or transmission temperature? The transmission can take it, you just want to change the fluid a lot sooner after the trip. You can certainly install a larger external trans cooler and or put in a lower temperature thermostat for the cooling system. The problem with most aftermarket thermostats is that they are unreliable.

How much weight are you towing? What does the Denali weigh fully loaded on those trips?

 

[BG1988]

What is best way to lower engine temp while driving or towing in hot Arizona conditions? Should I install a bigger transmission cooler in place of stock cooler? I’m trying to avoid hitting 235 degrees while towing. Any advice?

2500HD series
Max Trailering Package

 

[Joseph Garcia]

Welcome to the Forum from NH.

Folks are already chiming in with their suggestions and perspectives, and I'm sure that other folks will chime in as well.

 

[Klewis]

Welcome to the forum Kirk. See post #290 in this thread: https://www.tahoeyukonforum.com/threads/useless-information.97483/page-29

Is 235 the coolant or transmission temperature? The transmission can take it, you just want to change the fluid a lot sooner after the trip. You can certainly install a larger external trans cooler and or put in a lower temperature thermostat for the cooling system. The problem with most aftermarket thermostats is that they are unreliable.

How much weight are you towing? What does the Denali weigh fully loaded on those trips?

Welcome to the forum Kirk. See post #290 in this thread: https://www.tahoeyukonforum.com/threads/useless-information.97483/page-29

Is 235 the coolant or transmission temperature? The transmission can take it, you just want to change the fluid a lot sooner after the trip. You can certainly install a larger external trans cooler and or put in a lower temperature thermostat for the cooling system. The problem with most aftermarket thermostats is that they are unreliable.

How much weight are you towing? What does the Denali weigh fully loaded on those trips?

The 235 is the engine coolant. I tow a trailer to San Diego that weighs about 6000-7000 lbs and my Denali hits 235 on freeway with slightest uphill grade. I’ve read on this forum that the engine runs hot and that is normal but it always freaks me out . I’m not sure what the Denali weighs fully loaded. I will eventually buy a diesel to tow but have to keep using the Denali in mean time.

I’m trying to keep the wear and tear down on engine and I figured extended trips towing and running engine at 235 would not be good.

Also, I don’t remember exact trans temp but it was definitely closer to 230-240 on the hills. I was thinking if I lowered the trans temp my engine coolant would run cooler as well. Am I way off?

I’ll review that thread you linked as well. Thanks!!

 

[swathdiver]

The 235 is the engine coolant. I tow a trailer to San Diego that weighs about 6000-7000 lbs and my Denali hits 235 on freeway with slightest uphill grade. I’ve read on this forum that the engine runs hot and that is normal but it always freaks me out . I’m not sure what the Denali weighs fully loaded. I will eventually buy a diesel to tow but have to keep using the Denali in mean time.

I’m trying to keep the wear and tear down on engine and I figured extended trips towing and running engine at 235 would not be good.

Also, I don’t remember exact trans temp but it was definitely closer to 230-240 on the hills. I was thinking if I lowered the trans temp my engine coolant would run cooler as well. Am I way off?

I’ll review that thread you linked as well. Thanks!!

Are you viewing that temperature via the gauge on the dash or another way by chance? You can go to a 60/40 water to coolant mix to bring the temps down some. A larger trans cooler may help a little, it will help the trans more than the motor temps. Does your truck have an engine oil cooler too? If not sure, are there 1/2 inch lines running into the radiator tank on the driver's side?

@Doubeleive Wes, did your Denali come with the little 500 watt fans or was it just the fewer blades? Thinking of ways Kirk can cool his truck down while towing. Show him your Tru-Cool if you don't mind.

 

[Klewis]

Are you viewing that temperature via the gauge on the dash or another way by chance? You can go to a 60/40 water to coolant mix to bring the temps down some. A larger trans cooler may help a little, it will help the trans more than the motor temps. Does your truck have an engine oil cooler too? If not sure, are there 1/2 inch lines running into the radiator tank on the driver's side?

@Doubeleive Wes, did your Denali come with the little 500 watt fans or was it just the fewer blades? Thinking of ways Kirk can cool his truck down while towing. Show him your Tru-Cool if you don't mind.

I have 1/2 inch lines running to top of radiator on drivers side. I was reading temps from gauge in Denali so probably not super accurate. I think I need to upgrade to a 2 or 3 core radiator and a bigger trans cooler. I have the dual electric fans.

 

[Doubeleive]

Are you viewing that temperature via the gauge on the dash or another way by chance? You can go to a 60/40 water to coolant mix to bring the temps down some. A larger trans cooler may help a little, it will help the trans more than the motor temps. Does your truck have an engine oil cooler too? If not sure, are there 1/2 inch lines running into the radiator tank on the driver's side?

@Doubeleive Wes, did your Denali come with the little 500 watt fans or was it just the fewer blades? Thinking of ways Kirk can cool his truck down while towing. Show him your Tru-Cool if you don't mind.

mine came with the dual 500w 5 blade fans, and the oem trans cooler was a little itty bitty thing
kirk you can check you glove box for the list of codes and see if one of them say's K5L (heavy duty cooling package) , if it's not listed then you can upgrade the oem cooling fans to the dual 700w used ones are generally about $125 (they are plug-n-play) and you can add a true-cool 40k transmission cooler fairly easily as well those also run about $125 (new) I do not tow anything regularly but I do drive it pretty hard here in central California and with the true-cool and a B&M deep transmission pad my trans temps dipped from 220 way down to 165 usually it's less depending on the season 120-135, I can make it get to 180 if I try really really hard but it's hasn't gone past that since. Engine has never budged except once up at about 8000 feet it went up to maybe 230 because I was pushing it 90+ on big upgrades and it was 70deg's out in the summer at that elevation, even then the trans temp stayed at 165.

 

[swathdiver]

mine came with the dual 500w 5 blade fans, and the oem trans cooler was a little itty bitty thing
kirk you can check you glove box for the list of codes and see if one of them say's K5L (heavy duty cooling package) , if it's not listed then you can upgrade the oem cooling fans to the dual 700w used ones are generally about $125 (they are plug-n-play) and you can add a true-cool 40k transmission cooler fairly easily as well those also run about $125 (new) I do not tow anything regularly but I do drive it pretty hard here in central California and with the true-cool and a B&M deep transmission pad my trans temps dipped from 220 way down to 165 usually it's less depending on the season 120-135, I can make it get to 180 if I try really really hard but it's hasn't gone past that since. Engine has never budged except once up at about 8000 feet it went up to maybe 230 because I was pushing it 90+ on big upgrades and it was 70deg's out in the summer at that elevation, even then the trans temp stayed at 165.

Thanks Wes. I find it odd that GM didn't give all the Denalis the 700 watt fan motors. Even my little 5.3 has them!

 

[Doubeleive]

another thing to consider also is the radiator, my personal recommendation is if the radiator is 5 years old or older then replace it, run some citric acid thru the system and flush everything out real good, use a good brand name radiator or a new oem one, the cheapy ones have problems.

here is the fans you can use dual 700w 7/9 blade they will fit right on and plug in the same and nothing else needs to be modified.
https://www.ebay.com/itm/2009-Cadil...Hummer&hash=item4b777f85e3:g:3wkAAOSwiiZei1fQ

and the true-cool
https://www.ebay.com/itm/Tru-Cool-M...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

 

[gooffeyguy]

Do the fans on these trucks still run when at highway speeds? I know many cars don't, only when below a certain speed

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[Doubeleive]

Do the fans on these trucks still run when at highway speeds? I know many cars don't, only when below a certain speed

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

don't know, never watched the tech2 data for that

 

[BG1988]

don't know, never watched the tech2 data for that

if it's running hot run the heater with the windows open that is a old trick in the book to do when it's overheating

 

[Foggy]

The fans do run at any speed IF commanded by the PCM at the temps that
are preprogrammed.
You could/should do something about 235 temps while moving at speed.
New or upgraded radiator. Trans cooler or Trans Pan (deeper)
Better fans if yours dont have them. Make sure your coolant
is correct. In kalifornia, I'd think a 60%-70% water to dexcool would be good and
use an additive like lubegard or redline for coolant.
Also, you could go with a 180* Tstat and program your fans to come on earlier with
a handheld programmer like a diablosport or similar
Water Pump is also an easy replace if yours is original, might not be as efficient too

 

[BrainDead]

The 235 is the engine coolant. I tow a trailer to San Diego that weighs about 6000-7000 lbs and my Denali hits 235 on freeway with slightest uphill grade. I’ve read on this forum that the engine runs hot and that is normal but it always freaks me out . I’m not sure what the Denali weighs fully loaded. I will eventually buy a diesel to tow but have to keep using the Denali in mean time.

I’m trying to keep the wear and tear down on engine and I figured extended trips towing and running engine at 235 would not be good.

Also, I don’t remember exact trans temp but it was definitely closer to 230-240 on the hills. I was thinking if I lowered the trans temp my engine coolant would run cooler as well. Am I way off?

I’ll review that thread you linked as well. Thanks!!

If you're overheating at hwy speeds on semi flat terrain, a lower thermostat and heavy duty cooling fans ain't gonna do much, show me how an electric fan can pull more air through the radiator than doing 65mph on the fwy...

You've obviously have other issues going on and I'm guessing it's a clogged radiator, been there with my 02 2500 Sierra with a 6.0L

Can you post up some vehicle info i.e. year, mileage, maintanence records on cooling system

 

[avalonandl]

Yeah flush the radiator and also check for debris in the cooling fins blocking air flow.

The water pump maybe failing too....very common

 

[petethepug]

Good thing your on top of this. The radiator fins can be clogged on you’d never know it until it’s removed and held up to the sun.

The underhood temps in these trucks can get out of control because of heat soak. You’d due well to look for an oem style, all metal radiator with an extra row. It’d help out two fold. You’d have insurance against failures known to occur from the plastic tanks cracking due on high load and know it’s operating at 110% efficiency.

Increase the size of the trans cooler and relocate it away from the radiator/ condenser area. You’d stop the heat of the trans cooler from being passed into the a/c & coolant system. That adds to the trans cooling capacity and keeps the trans cooler heat exchange out of the system load.

Adding a water wetter to the radiator fluid upon flush out would really add an unmatched layer of protection and keep the pressures within tolerance to stave off hose and fitting damage.


Sent from my iPhone using Tapatalk

 

[rjr]

Do not overlook what swathdiver said above: switch to 60% water/40% antifrreze. While that lowers the boiling temp, it also raises the specific heat of the coolant mix and it can remove more BTUs of heat from the engine, causing it to run cooler. Learned this years ago from running tests on my twin engine cabin cruiser, after a chemist friend alerted me to the the specific heat issue.

 

[Foggy]

Just to add: Water cools/ dissipates heat better than antifreeze.
But of course you need some amount of antifreeze for is lubrication and anti
corrosion properties.
In my summer fun vehicles I run only about 20% antifreeze with 80% distilled
water and an additive like lubegard/water wetter/ etc

The specific problem in this case is probably a gooped up radiator - inside AND Outside
And maybe an old mixture of coolant

 

[Monz11]

mine came with the dual 500w 5 blade fans, and the oem trans cooler was a little itty bitty thing
kirk you can check you glove box for the list of codes and see if one of them say's K5L (heavy duty cooling package) , if it's not listed then you can upgrade the oem cooling fans to the dual 700w used ones are generally about $125 (they are plug-n-play) and you can add a true-cool 40k transmission cooler fairly easily as well those also run about $125 (new) I do not tow anything regularly but I do drive it pretty hard here in central California and with the true-cool and a B&M deep transmission pad my trans temps dipped from 220 way down to 165 usually it's less depending on the season 120-135, I can make it get to 180 if I try really really hard but it's hasn't gone past that since. Engine has never budged except once up at about 8000 feet it went up to maybe 230 because I was pushing it 90+ on big upgrades and it was 70deg's out in the summer at that elevation, even then the trans temp stayed at 165.

I pulled the trigger on a Mishimoto radiator, B&M deep tranny pan and ended up with the derale tranny cooler. My Hoe has the puny dual 5 blade fans, but I do have the K5L code, any advice on aftremarket cooling fans? Or are these OEM ones 700W? I was going to take your suggestion on the 7/9 esky fans, but not an electrical geek?
Thanks