2007 Yukon Denali overheats and turns off AC...

[Doubeleive]

I bought mine from 1800radiator because it was the only one that was 1 3/8 and had both oil cooling and transmission cooling, then I upgraded my fans to the dual 500watt, I am in the central California valley where it gets plenty hot in the summer.

 

[Warriorpluto]

What's a k5l? New body style?

 

[swathdiver]

What's a k5l? New body style?

No sir, it's the Enhanced Cooling Package. It includes the most powerful fans, a larger radiator, an engine oil cooler, an external transmission cooler and lower gears for towing among other things.

 

[Warriorpluto]

No sir, it's the Enhanced Cooling Package. It includes the most powerful fans, a larger radiator, an engine oil cooler, an external transmission cooler and lower gears for towing among other things.

Oh ok I don't know. I'll have to look. The codes were torn off of my glove compartment

 

[puckhead]

Truck has overheated twice since my last post. Took it to a shop who couldn't replicate it, no surprise there. They cleaned the throttle body, intake, etc. They also put some fuel system cleaner in, no clue what type though. I haven't taken it on a long drive since.

I might look into a new water pump. Any suggestions for brands?

 

[swathdiver]

Truck has overheated twice since my last post. Took it to a shop who couldn't replicate it, no surprise there. They cleaned the throttle body, intake, etc. They also put some fuel system cleaner in, no clue what type though. I haven't taken it on a long drive since.

I might look into a new water pump. Any suggestions for brands?

GM OE (Original Equipment) or AC Delco Professional as a second choice.

Like Wes has said, it could be a radiator. I reckon the fins get clogged but internally, if the system was ever compromised, sludge can form and of course clog the passages on the inside.

Offhand, I do not know how to test for a bad radiator or water pump with no visible defects. Anyone?

Do what you can to not create stress for your wife while she's with child.

 

[puckhead]

GM OE (Original Equipment) or AC Delco Professional as a second choice.

Like Wes has said, it could be a radiator. I reckon the fins get clogged but internally, if the system was ever compromised, sludge can form and of course clog the passages on the inside.

Offhand, I do not know how to test for a bad radiator or water pump with no visible defects. Anyone?

Do what you can to not create stress for your wife while she's with child.

Thanks for the input! She is driving my truck now, but its an F350 that drives rough compared to the Denali lol. I just have to figure out what to spend money on first now. When I flushed the radiator it seemed to flow pretty good. The fluid was also pretty clean. I guess there could still be a clog in there from sometime before. Just thinking out loud now.

Any such thing as an upgraded/high flow water pump for these trucks that would be a bit better than OE?

 

[swathdiver]

Thanks for the input! She is driving my truck now, but its an F350 that drives rough compared to the Denali lol. I just have to figure out what to spend money on first now. When I flushed the radiator it seemed to flow pretty good. The fluid was also pretty clean. I guess there could still be a clog in there from sometime before. Just thinking out loud now.

Any such thing as an upgraded/high flow water pump for these trucks that would be a bit better than OE?

Yeah, that one ton Ford might induce labor! LOL

I used to make deliveries all day in a '99 with a stake bed, I was beat up at the end of the day. I only chose it over the same year Chevy because the cab was bigger, more room for my gut!

As for the water pump, don't know, never looked.

I don't think you need to upgrade over stock, just to restore whatever is worn back to stock specs.

 

[gpracer1]

Im seeing two people here having the exact same problem?
Is it "overheating" when driving slow in the city or at highway speeds?
Is the fluid boiling out or any loss/overflow?
Is it REALLY overheating or is it a sensor/electrical problem?

Full coolant, new thermostat, fans working would all indicate low water flow either clogged radiator (usually hot under load like freeway) or water pump not turning/belt slip/impeller worn, etc.
Would love to see what the actual water temp is with a separate thermometer.
This is all assuming there is no grocery bag sucked up in the front.

 

[puckhead]

Im seeing two people here having the exact same problem?
Is it "overheating" when driving slow in the city or at highway speeds?
Is the fluid boiling out or any loss/overflow?
Is it REALLY overheating or is it a sensor/electrical problem?

Full coolant, new thermostat, fans working would all indicate low water flow either clogged radiator (usually hot under load like freeway) or water pump not turning/belt slip/impeller worn, etc.
Would love to see what the actual water temp is with a separate thermometer.
This is all assuming there is no grocery bag sucked up in the front.

I'm fairly sure its overheating, I'm no mechanic though lol. Ours has all been highway speeds then to a random stoplight where it dies. No loss of fluid but it is very hot and sound like it was bubbling/boiling at least once. Is there special thermometer to use for what your'e talking about? I assume I wouldn't open the cap when it is overheating and stick it in lol