PFSER

I have a 2007 Suburban 2500 with a 6.0L gas motor that has about 72k miles on it. I purchased the truck with about 68k miles on it and noticed the temp gauge would creep up during idle (bank lines, etc.). Didn't think much about it until I towed my 32' travel trailer and the temp gauge ran up to about 250. The temp gauge will show nearly 3/4 (about 235) if driving around town on a hot day with A/C on. If I tow even a small open trailer with a light load, its worse. According to the operator's manual and the dealership "this is all normal and I shouldn't panic until warning lights start coming on."

I performed a self-flush and hosed out the radiator (no improvement), replaced the clutch fan (no improvement), and had the dealer perform a full coolant flush (still no improvement!).

It seems to me there is an obstruction somewhere. Has anyone else had this issue, and if so, what fixed it? I have another trip planned with my travel trailer and don't want to be stuck on the side of the road because of an overheated motor.

Thanks in advance...

hicksvilleshick

I would replace the t-stat, blast out the fins in the radiator if you can, and make sure it's full.

73shark

Welcome to the forum.

That was my first guess also. The t-stat is probably sticking. These NBS should hardly ever go over 210*F. Maybe w/ that tow load it might go a little higher but 250*F seems a bit much. What's the trailer weight?

kevinkpk

I also agree with thermostat. Pulling a trailer you might want to drop from (guessing) 195-180 deg. Flushing is good, but thermostats AND CAPS are cheap.

LTL4life

Mine runs a consistant 195. On a long 950 mile trip out east in the dead heat of July with temps at 100 deg. with the air on, the Edge CS showed a constant 195 deg.
I have 80,500 miles on mine

SWHouston

You might try a Temperature Verification...

If you have one of those stick Thermometers for A/C, just pull the Radiator Cap off when cold, stick the Thermometer into the Radiator fluid, and crank it up. Just watch what the Thermometer reads, and check inside to see if the Gage is in reasonable compliance. You may have to remove some of the Coolant to see into the Radiator Header.
Siphon or suction, you can put it back in later.

You shouldn't have to worry about a overflow, since the Thermostat is below 212°. Also, when the Thermostat opens, you can verify/see a good rolling/flowing of the coolant in the Radiator.

Just make sure you put the Radiator Cap back on, BEFORE, you shut the engine off.

yukondean

i have a 2007 yukon xl 2500 that behaves exactly as you describe and has since it was new. the dealer has tried many things but has not yet found it. if you have temperature display in your rearview mirror watch it during the event. you will notice that the temepearture goes way up. for some reason the clutched fan is not engaging so the temperature in front of the radiator (where the ambient temp sensor is) goes way up. The AC is automatically shut down and the engine is detuned and power drops. my clutch has been replaced 3 times, the latest last week, and the probelm persists. this is one of 2 problems that exist with this vehicle. the second is very dangerous and your car has it. under perfectly understood conditions, your car will shut down when the tank is just above 1/4 tank and act as if it out of fuel, but it is not. you will lose power steering, most braking and will not have engine braking. it has happened to us many many times. you will have to add gas to the tank to get it started. if you are towing down hill this could be fatal... GM is aware of this issue

RacerX

All of the above PLUS why dont you add an extra fan in front of the radiator assembly to force air past it to aid in cooling? Your local stereo guy can hook that up simply.

samjacob1988

Did anyone figure this out did replacing the the thermostat solved it. I have the same issue I live in az its pritty hot here I dont know why chevy didnt install an electric fan with the mechanical fan to help the cooling. The thermo guager runs over half.

SWHouston

It's unfortunate that we don't often get followups. Here's a cut/paste from another Post on issues which may cause overheating.

DIYTASKS:
1)Establish that the Fan Clutch is operating properly by hand (cold turnsfreely)(hot turns with resistance). If you don't have a Clutch Fan, then skipthis step.

2)Check the tension on all Belts (Serpentine/V). There may be a rare need to usea Spray on them, which limits slipage.

3)Operate Cabin Heater(s) full hot. And establish that there are no pockets ofAir captured in cooling system.

4)Make sure that ALL hoses aren't collapsing (have good internal wire support) Collapsemost obvious when the engine has cooled completely.

POSSIBLESHOP ASSIST:
5)Use/have the Coolant proportion tested with an Antifreeze Tester. 50/50% customarilygives you the best transfer of heat, but, follow the directions of the CoolantManufacturer for best results.

6)Take Vehicle by a Radiator Shop, and have them check/sniff the headroom/air inthe Radiator for any Fuel Gas which may be leaking into the Cooling System.Even a small amount, which won't/doesn't immediately affect your Reservoirlevel, can make a large difference in cooling system.

7)Do a good Clean/Flush on the Cooling System. (back-flush Heater Cores as well).

8)See that the Thermostat is opening fully at the recommended temp. (place it inhot water and check with a Thermometer).

9)Have the Radiator Cap tested for proper pop-off/release pressure and gasketintegrity (or just replace it).

10)Do a thorough visual inspection of your Water Pump (or just replace it) andmake sure that the blades are in good condition, and able to drive the Coolantwith sufficient volume.

11)Rod/pro clean the Radiator, and make sure that it's the one that should be onyour vehicle. You also should search for another Radiator which had more tubes(thicker) which is designed to cool better (frequently found on vehicles whichhave "Cooling Packages" installed).

PARTSCHANGE:
12)You could increase the number of blades on your Fan. I've seen Fans which hadas many as Eleven blades. Nine blades ismore usual for extra cooling. This type Fan can move a LOT of air at slowspeeds/RPM's. This applies to Clutch or Direct Shaft Driven Fans.

13)Install a "smaller" sheave/pulley for the Fan. Smaller diameter willdrive the Fan and Pump faster.

14)Consider (if Auto-Trans Equipped) to separate/divert the Transmission Oil outaway from the Radiator, to an Add-On Cooler of its own. There's more than oneway to do this (requires further discussion).

15)Install Thermostatically controlled Booster Electric Fans ahead of theRadiator-A/C Condenser.

Itemshave been categorized for convenience, you may do any of these proceduresyourself, and the purchase of Tools or Testing Equipment would be necessary.