Towing Temperature

[1500Josh]

Issue: Overheating only while towing

Truck: 2002 Dodge Ram 1500 SLT 4x4 - V8 5.9
Miles 240,000
- Engine was replaced a Junkyard Engine (BnR) in good condition 140k miles
- 46RE Transmission replaced with Junkyard Engine (BnR) 130k miles

Purchased used truck with the sole intention of towing a travel trailer only.

Time table:
April30th 2024: Towed Travel Trailer for the first time with temperatures approaching HIGH mark on temperature gauge - Towing 40 miles on flat ground
May15th 2024: Replaced Radiator, Water pump, + new fluids: TEMPERATURE 3/4 on temperature gauge (see photo)-- Only towing 50 miles with a slight grade on I5 for stress test
Jun22nd 2024: Replaced Thermostat from 195F to 180F and Fan clutch -- Towing the same 50 miles with a slight grade and the temperature gauge reached ~3/4 temperature

-While towing OD is off
-Only in 2wd while towing
-Temperature conditions were 85 F
-Travel Trailer Dry weight is 4500 lbs (only used when stress test the towing)
-We live in the valley and plan to tow up steeper grades and through mountains.
-No VISIBLE signs of HeadGasket issue as oil remains clean

Concern:
Is it fair to surmise that if I take this truck up through the mountain passes, that it will only climb in temperature and eventually OVERHEAT PAST temperature gauge where damage can be done to the engine and other components?

Main Questions:
What could be a cause for this constant overheating while underload and is it normal for trucks to do this? This is my first experience towing this large of a haul and unsure if this is expected.

Is it possible that the truck is not cut out to tow this large of a haul although it is within its specifications?

It is worth noting that the truck drives great with and the engine and gear shifting is not a problem. No overheating while driving dry. While towing the acceleration is almost non-existent but that is expected, right?

 

[jws123]

Does it overheat while driving normal not towing?

Your going to blow your engine/head gasket if you keep running it that hot at no point should it go past 1/2 you have a issue. As it is you may want to test your head gasket they sell the kit online but Check your clutch fan to make sure its working even tho you said its new aswell as your thermostat you may also want to burp the system again.

 

[1500Josh]

To be honest, I have never driven that far while not towing. I have only driven it 50+ miles while towing. Within 20-30 miles non-towing it remains at normal temperature, below 1/2.

I will try to burp it again today and check into the head gasket kits.

 

[BenchTest]

What kind of RPMs are you running while towing out of OD?

 

[1500Josh]

It runs between 3-4k. probably closer to 4 k when OD is off

 

[sony224422]

You might want to check the inlet and outlet of your radiator. Your clutch fan can be checked too.

While I have a hemi, I tow 10k on a gooseneck and will hit that temp pulling a hill. Watching it on a scan tool, 3/4 is roughly 215° for me. While that is warmer than what is normal, it drops fast when the rpm’s drop back down. I would see if driving normally you overheat.

You can grab a heat gun too and measure the radiator. You can use it for your trailer wheel bearings too

 

[1500Josh]

I am not sure if I should be relieved or even more confused. I drove today unloaded for 70 miles on the same route that triggered the trailer to OH. The heat gauge did not get to the halfway mark.

I fully expected there to be some overheating to occur.

I ordered a Gasket test kit as suggested by JWS and hopefully that is negative tomorrow.

I will probably consider the scan tool for temperature monitoring. Can you link the one that you suggest?

 

[Smokeybear01]

I am not sure if I should be relieved or even more confused. I drove today unloaded for 70 miles on the same route that triggered the trailer to OH. The heat gauge did not get to the halfway mark.

I fully expected there to be some overheating to occur.

I ordered a Gasket test kit as suggested by JWS and hopefully that is negative tomorrow.

I will probably consider the scan tool for temperature monitoring. Can you link the one that you suggest?

I picked one up at Harbor Freight for under 20 bucks a while back for checking wheel bearing heat. It works good and the grandkids really enjoy playing with it.

 

[wrench78]

Your truck may not be setup for towing. For instance. You may not have the proper engine/transmission coolers for towing. That would be my guess. Most trucks that are setup for towing have heavy duty cooling systems.

 

[jws123]

Your truck may not be setup for towing. For instance. You may not have the proper engine/transmission coolers for towing. That would be my guess. Most trucks that are setup for towing have heavy duty cooling systems.

Could be the case however I towed tripple axle boats/trailers and car trailer with my older 3rd gen 1500 and never had a issue. I had the hemi tho I still think he has a bigger issue going on would however be a good idea to install a aftermarket trans cooler if you tow alot.

 

[ppine]

Try a lower temp thermostat. Boil out or replace your radiator. You are asking for problems to run it like it is.