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Engine getting hot when towing

Chris_G1

Full Member
Joined
Jul 14, 2010
Messages
212
Location
Burlington, Ontario, Canada
I have had my ?07 for close to 10 years now and have pulled the same travel trailer for all those years. In the last 2 years when I'm pulling the trailer the temperature gauge is fluctuating up and down quite a bit and gets as high as the 3/4 point. I do have the coolant changed regularly and i have had it in at looked at twice for this situation and both times I'm being told everything coolant related is functioning as it should be. I do trust the shop i take it too, but it bothers me that in all these years of ownership towing the same trailer that this is a new problem, in the past the temperature gauge needle never went past the half way point. This is also only related to pulling the trailer, I regularly in the summer months travel without the trailer and on 3hr highway trips it never shows getting hot.

Any ideas? Anyone else gone through this ?
 
I regularly flush the cooling fins of the radiator. I use some foamy engine cleaner and spray the front of the radiator then use a garden hose and flush it out from inside of the engine compartment thru the fans.

Another thing you may want to check are the fans, make sure both of them are coming on.

If you are using the AC it may be the compressor cycling on and off.  HTH
 
Thanks for the suggestions, i do need to give it a wash today i will try washing off the rad, i have never done it so even if its not the cause its a good idea.

As for the fans when i had it to the shop last week and last year for this problem they said they had tested them and they too are functioning as they should be

The air conditioning is usually on, but again everything in the years of ownership remain the same, same truck, same trailer, close to the same weight in luggage and passengers, definitely not fluctuating by 100?s of pounds
 
You'll be surprised what comes out of the radiator Flies, Bees, tree pollen, fish flies and dirt.
 
Check between the AC condenser and the radiator for debris also.  R.
 
  Hoses, thermostat, and belts.
Hose can collapse, thermostat, hoses wear out over time. 


 
JVZL1 said:
  Hoses, thermostat, and belts.
Hose can collapse, thermostat, hoses wear out over time. 



I did wonder about these things, obviously when pulling the trailer things get hot fast, but if it did happen to be a failing hose or thermostat would it not have A. completely failed after 2years or B. Would it not show the symptoms of overheating on a long highway run even when its unloaded?

I guess for the cost of the stat and hoses its worth the change anyway on a truck that 11 years old
 
Have you monitored the transmission temp over the years?  I wonder if your tranny is running hotter.  Since there is a tranny cooler built into the radiator (the transmission is the first thing cooled by the coolant/radiator) I wonder if much hotter transmission fluid is heating up the coolant coming out of the radiator more than it has in the past?
 
enoniam said:
Have you monitored the transmission temp over the years?  I wonder if your tranny is running hotter.  Since there is a tranny cooler built into the radiator (the transmission is the first thing cooled by the coolant/radiator) I wonder if much hotter transmission fluid is heating up the coolant coming out of the radiator more than it has in the past?

Unfortunately i have never monitored the temps with anything other than the gauges from time to time as im driving. Nothing has ever jumped out at me as being out of the ordinary from what the DIC tells me.

Having said all of that i am a beliver in changing my transmission fluid frequently I believe i am do now for a change, but when this problem started the fluid was only w or 3 years old
 
Changing the coolant is good, but eventually a flush will be beneficial. Recover the coolant, flush with water, recover, add a flushing chemical and water, run for 20 or 30 minutes, allow to cool, recover, flush with water, recover, then final fill with coolant. A good flush can really help the heat transfer.
 
buickwagon said:
Changing the coolant is good, but eventually a flush will be beneficial. Recover the coolant, flush with water, recover, add a flushing chemical and water, run for 20 or 30 minutes, allow to cool, recover, flush with water, recover, then final fill with coolant. A good flush can really help the heat transfer.

That's a good idea, I had a 2000 S-10 years ago that I didn't change the coolant enough and the Dexcool hardened and created a blockage at the heater core which is another reason why i like to change it in the Avalanche every couple years. With its age I suppose there could be some buildup causing issues
 
Never use tap water when doing anything in your vehicle. If you, or the shop you have been using, have been using tap water it can coat your coolant system with chemicals in the tap water. Only used distilled or otherwise purified water that has had everything taken out.

Tap water contains many added chemicals that the water plant adds to protect piping and treat the water. This stuff is NOT compatible with the coolant system in your vehicle and repeatedly using tap water can and will coat the whole system. (See Flint, MI and what happened when they didn't add phosphates to their water... Those coat the pipes as well as your radiator etc...)

If your towing you should try adding a transmission temp sensor. It will tell you if your having issues with your transmission long before you feel them. As Enoniam mentioned. If the transmission is getting hot it will certainly reduce the radiators ability to cool the engine.

Someone that rebuilds clusters such as dashdr.com can add the extra motor, the overlay and needle you need. He can also reprogram the cluster if it needs it. You MAY find if you add the new overlay, the motor and needle yourself that your cluster MAY support transmission temp already. I know mine did...

 
If you have one available, or just need an excuse to buy one, check the radiator temperature with an infrared non-contact thermometer. Start at the inlet side of the radiator with the engine running and up to operating temp, and move across the radiator side to side, in a serpentine motion until you reach the outlet. If you reach a cool spot towards the bottom, or corners of the radiator, them you have a blockage. You can try to flush it, but you'll most likely wind-up changing out the radiator. Most of the flushes sold today aren't all that robust. I've seen people with oil/trans coolers leak or bad turbos on HD over the road trucks use cheap, powdered dishwashing detergent as a flush. Probably wouldn't hurt to swap in a new thermostat either, they can get stuck, or slow to react, and the added load of the trailer might be just the thing to make it run hotter. Good Luck
 
I just got back from a weekend camping trip, towing the trailer and still the temp gauge is running between half and up to 3/4. I got out of the truck while it was running after driving for an hour + and i did hear the fans coming on. It was hot today, truck said 93 degrees so i guess the cooling fans are doing their jobs since im not fully overheating.

Another thing i did notice today, and when i think of it have noticed it in the past and im wondering if they are related, i had to make a left turn from a dead stop up a slight incline and in tow/haul mode there was a major lack of power, pedal to the floor and it was taking forever to get up to speed. It doesnt seem to happen very often, most times when i pull from a dead stop with the trailer i feel i have more than enough power to get the truck and 5000 pound trailer moving, but every once in a while pulling from a dead stop it feels horribly underpowered
 
power or tranny slipping?
 
ygmn said:
power or tranny slipping?

If it was slipping i would imagine the RPM?S would be way higher than the speed is indicating?

If so its a lack of power because the RPM?S are staying low

I did just go out and check tge trans fluid and its still nice and red, personally I believe its time for a change, it was last done about 5 years ago, but it?s definitely not burnt at all
 
I had an issue a couple weeks ago which resulted in the changing of my crankshaft position sensor and my throttle body. Went camping this past weekend towing the trailer and the temperature gauge didn't move at all, the truck even feels different like it has more power and it's not struggling, which was a complaint of mine.
 
You'll be surprised what a dealer will do for you when you take it in for repairs. Most times they won't even tell you they did it.
 
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