Tow truck running hot when A/C on

[rechewjr]

Good afternoon all,


This is my first post so please be nice! My wife and I bought our first airstream at the beginning of June. It is a 2006 20' Safari with a UVW of 3,693lbs. I am using a 2006 Dodge Dakota Quad Cab 4.7l v8 with tow package to tow.


The specs lead me to believe this was a suitable tow vehicle however when towing and running the a/c the truck tends to run a bit hot.

Truck specs:

http://trailers.com/tow-capacity/ind...emplate=normal


I took it to the local a/c guy who said everything looks fine from the a/c side of the house and he thinks the truck may be undersized. This doesn't seem right to me.



Is it common for a truck to run a bit hot when towing like this? When I turn off the a/c the temp returns to just a bit above normal. Any help or where to start would be greatly appreciated. I'm open to anything at this point. Thanks.

[Kevin245]

I’m not going to go into the specifics of your towing combination. You say that things look good from the AC perspective, but have you looked at the engine cooling system? Your TV is 13 years old, as such I’d check the radiator, cap, thermostat, belts, and hoses. A thorough system flush and inspection would be my course of action.

BTW... We’re always nice.

[Overstreet]

What does "run a bit hot" mean? Is it overheating or not?

[Bill M.]

How hot? Does the tow package include a transmission cooler if it is a auto trans? I do not think it ought to “run hot” when towing. If it were me I would consider a bigger truck. Or a new radiator, WP, hoses, belts, etc and re evaluate it. And certainly a transmission cooler if an auto. I had a v 6 Dakota years ago. Ride terrible. No power. I liked the used f 150 that replaced it a lot better. Modern radiators corrode fast and can not be really cleaned or fixed. I would feed it a radiator if I liked the truck. It probably needs it anyway. Last year I put a radiator, WP, hoses, and belt on my 11 year old TV. Good for peace of mind on the road.

I guess I can not really answer your question. If the gauge goes up a little on pulls and drops back to normal on flats that is probably fine. You are putting a significant load on it. My justification for work that may or may not be absolutely need at the time is “would I rather do it here or on the interstate with the trailer in tow”

My best guess is that you do not have quite enough truck.

[GCinSC2]

Your dash gauge, real gauge?

A tool that might be of interest to get a digital engine temp plus three additional engine functions from a long list is a Scan Gauge It plugs into OBD port and then position where you want it. Go thru setup select monitored and displayed functions and start driving.

It taps into vehicle system and reports what the system is seeing also reads codes and slices tomatoes really thin. Kidding.

I’ve got one on my Bug and use it in particular to monitor engine temp.

Next diagnostic tool if you’re a DIY guy an IR temp gauge very helpful in sorting out temp issues brake and tire temps and checking the skillet for pancake temp.

Gary

[thewarden]

Originally Posted by Kevin245

I’m not going to go into the specifics of your towing combination. You say that things look good from the AC perspective, but have you looked at the engine cooling system? Your TV is 13 years old, as such I’d check the radiator, cap, thermostat, belts, and hoses. A thorough system flush and inspection would be my course of action.

BTW... We’re always nice.

Yes, this. On a 13 year old truck it could be any number of things including radiator fins blocked by debris and bugs, a cooling system that has never been flushed, thermostat not quite working right, low coolant levels etc. This will all be discovered and sorted with an inspection and system flush.

By the way, your engine will work a little harder when the a/c is running, so if everything is not up to snuff, this will cause the engine to run hotter when the a/c is on. I always turn my a/c off when pulling hills to keep things a little cooler and get a little more power from the engine as it is not operating the a/c pump.

[rechewjr]

Originally Posted by Overstreet

What does "run a bit hot" mean? Is it overheating or not?

From what other people have said, it would probably be a good idea to start with a ODB Link to get an idea of what temperatures it is actually hitting. It normally runs below halfway on the temp gauge w/o trailer. With trailer and ac running it goes up to almost 3/4 of the temp gauge. When I turn the ac off it comes back down...

[A W Warn]

Originally Posted by rechewjr

Good afternoon all,


This is my first post so please be nice! My wife and I bought our first airstream at the beginning of June. It is a 2006 20' Safari with a UVW of 3,693lbs. I am using a 2006 Dodge Dakota Quad Cab 4.7l v8 with tow package to tow.


The specs lead me to believe this was a suitable tow vehicle however when towing and running the a/c the truck tends to run a bit hot.

Truck specs:

http://trailers.com/tow-capacity/ind...emplate=normal


I took it to the local a/c guy who said everything looks fine from the a/c side of the house and he thinks the truck may be undersized. This doesn't seem right to me.



Is it common for a truck to run a bit hot when towing like this? When I turn off the a/c the temp returns to just a bit above normal. Any help or where to start would be greatly appreciated. I'm open to anything at this point. Thanks.

My vehicles run pretty much the same engine temperature, around 200-210F on the gauge, towing or not, AC on or not. Today when the ambient was in the high 90's, and yesterday up to 102F, I did not see any significant change.

The exception to heat gain in my truck is when towing up a steep incline. The transmission will go from normal ~180-190F up to ~230F towing up a 5% grade for miles.

PS:
Welcome to the AirForums

[Moflash]

Originally Posted by rechewjr

Good afternoon all,


This is my first post so please be nice! My wife and I bought our first airstream at the beginning of June. It is a 2006 20' Safari with a UVW of 3,693lbs. I am using a 2006 Dodge Dakota Quad Cab 4.7l v8 with tow package to tow.


The specs lead me to believe this was a suitable tow vehicle however when towing and running the a/c the truck tends to run a bit hot.

Truck specs:

http://trailers.com/tow-capacity/ind...emplate=normal


I took it to the local a/c guy who said everything looks fine from the a/c side of the house and he thinks the truck may be undersized. This doesn't seem right to me.



Is it common for a truck to run a bit hot when towing like this? When I turn off the a/c the temp returns to just a bit above normal. Any help or where to start would be greatly appreciated. I'm open to anything at this point. Thanks.

You need a larger radiator to run cooler.Not a big expense and easy to replace.

[ITSNO60]

Originally Posted by rechewjr

From what other people have said, it would probably be a good idea to start with a ODB Link to get an idea of what temperatures it is actually hitting. It normally runs below halfway on the temp gauge w/o trailer. With trailer and ac running it goes up to almost 3/4 of the temp gauge. When I turn the ac off it comes back down...

Yes you definitely need a real gauge, or if your ECM reports coolant temp read it that way, some vehicles do not use ECT for ECM reference but rather oil temp in which case you will get an erroneous reading from the OBD system for ECT. You could try Torque Pro first, $5 for the app and a $15 ELM327 Bluetooth adapter from ebay and you are in business. Course if your ECM does not report ECT you will have to install a mechanical gauge (I went with DiPricol but they are out of business now, Isspro would now be my choice)

Many factory dash gauges are stepped, they are not actual gauges at all but merely have several steps and when you cross a threshold the needle moves to the next step. Historically automakers don't want you to know too much to avoid un-necessary warranty complaints but I noticed more new vehicles actually have real temp gauges with numbers on them.

As others have said you are working that truck hard, you might just have to turn off the AC when climbing and as needed.

[ddhisself]

Originally Posted by rechewjr

Good afternoon all,


This is my first post so please be nice! My wife and I bought our first airstream at the beginning of June. It is a 2006 20' Safari with a UVW of 3,693lbs. I am using a 2006 Dodge Dakota Quad Cab 4.7l v8 with tow package to tow.


The specs lead me to believe this was a suitable tow vehicle however when towing and running the a/c the truck tends to run a bit hot.

Truck specs:

http://trailers.com/tow-capacity/ind...emplate=normal


I took it to the local a/c guy who said everything looks fine from the a/c side of the house and he thinks the truck may be undersized. This doesn't seem right to me.



Is it common for a truck to run a bit hot when towing like this? When I turn off the a/c the temp returns to just a bit above normal. Any help or where to start would be greatly appreciated. I'm open to anything at this point. Thanks.

It has been my experience that the most common cause for overheating, assuming cooling system is clean and functional, is the fan clutch. I have had No luck with aftermarket clutches. bite the bullet and get one from Dodge.

[suncoasteng]

You most likely need a new water pump and new , and larger, radiator.
When towing, the engine works harder and gets hotter, so the radiator gets hotter, then the AC Condensor that is mounted right in front of the radiator runs hotter and you get less cooling in the cab.

[cwf]

Ever clean the radiator fins??? Many bugs in there and dirt will restrict. Need real temp to know. If AC not working well, you need to address the problem while you are at home, not on roadside without cell service

[Piggy Bank]

No one has mentioned payload, the oft overlooked variable in towing.

Are you carrying a lot of gear, people, dogs, tools, bikes, water, etc, or is your load pretty light?

I ask because sometimes people don't consider if they are maxing out the specs as loaded.

[PC Conner]

Just to check things, run the heater if the truck begins to overheat. That is not comfortable but will transfer heat out of the engine (and into the passenger compartment). This also may work in an emergency situation to prevent overheating and damage to engine until you can safely stop.
If overheating when stopping, let the engine idle for a bit. Once the engine is stopped, the engine temp will continue to rise. Idling will allow the coolant to circulate without the AC and load demand. Temp should drop. Turn the engine off once in normal range.

[CCWilson1]

I had an older version of the same tow vehicle, a 2000 Dodge Dakota Quad Cab with the Daimler-designed 4.7L V8 & gearbox and their towing package with "heavy duty" radiator and transmission oil cooler. I was towing horses back then, not an Airstream, but experienced the same run-hot problem you report. It was not just A/C that triggered higher than normal operating temperatures; any significant incline while hauling a load with ambient temps above 70°F would do it, even with the A/C off. On warm/hot climbs with a load, I would run the heater at full blast (it's a radiator too) but cooling stops under whatever shade I could find became the norm. I tried a few changes, including some of the suggestions here, (short of modifying the cooling system), but I concluded it was just an inadequate cooling system for any significant load. It was manageable until we moved to a higher elevation, where the problem was exacerbated by the reduced cooling of thinner air. I sold the truck to a relative who didn't need to haul heavy loads and bought a Colorado DuraMini.

[rechewjr]

Hello all,
Thanks for the great advice thus far. I finally got my odblink mx+ hooked up and tested it this morning. When not towing I am sitting around 203-208. I also noticed the air intake temp. was quite high--drove this morning in 75 degree weather and the air intake temp was up around 111. Is this normal for a truck? I ask as I also hooked the sensor up to my honda accord and noticed the air intake temp was close to the actual outside air temperature ~80 degrees. I'll post again when I hook up the trailer and get the temps while towing.

[batman]

perhaps a new fan clutch and cleaning the cooling fins?
-Dennis

[rechewjr]

Thanks so much everyone for all the replies and advice. It turns out it was the fan clutch. I replaced it yesterday morning then towed at 5pm while 97 degrees outside. When pulling a long incline with the ac running my temp went from 203 to 210. I heard the typical roar and the temp went back down to 208 and remained there throughout the tow. It did go back up after stopping for gas hitting 215 while climbing a hill, but again went back down once the clutch kicked in.

I was running around 225 before the replacement when just running the a/c while towing. Good to know I can keep using the truck -- may not be able to do the big mountains yet--will stick to the flatlands of south Georgia and Florida until we upgrade.

[ddhisself]

Yup! Fan clutch! Glad you got 'er going!