rkalisek

Accidentally posted to the wrong section, so here goes again.....

Hello all -- a newbie here, and not very mechanical!

I recently purchased a 2000 Grand Cherokee Laredo, I6 with what I thought was a factory towing package to pull my tent trailer. The trailer is a larger one, approximately 2600 lbs dry -- add 25 gallons of water, some gear and 2 occupants for less than 3600 gross probably?

Anyway, my spousal equivalent and I went camping last weekend for the first time with the Cherokee and the trailer. Most of the way to the destination was fairly normal in terms of climb or descent, but the last bit requires a reasonably steep climb, then a drop into the lake.

The temp outside was only mid 70's (according to the rig's data display). The AC was on, and I was towing with the OD off. Part way through the climb, I started watching the temperature gauge, and it was climbing past the 210 mark. I turned off the AC and kept watching. By the time we crested the ridge, the needle was WAY too close to the red zone for my comfort. I was grateful it was no hotter outside! It will be soon!

I've posed questions to the tent trailer forum, but thought I would here as well. I'm getting suggestions for everything from trans coolers to different fans and radiators. One of the simplest was to wash out the radiator, which I did -- though it wasn't overly plugged with bugs and large stuff, ALOT of grime washed out of it. How it will affect operating temp remains to be seen.

I felt I had talked to the seller enough about his experience with towing and overheating potential to be comfortable the vehicle would fit my needs well. Though I don't think I was misled, there are things emerging that I need to work out to feel comfortable towing safely and worry free.

Any suggestions you all might offer? Easiest and least expensive first, if possible -- Thanks much!!

Rob82

Hello start by checking that your electric fan is running when the ac is running the ac compressor adds "load" if you will to the engine making it work harder also the ac condenser (small radiator like part mounted I front of the actual radiator) heats up requiring more air to flow thru it aswell as the radiator to cool the freon and the engine coolant

The I6 motors generate a lot of heat I know a lot of the xj guys cut in hood vents to help vent the heat out of the engine compartment I'm not suggesting you cut into your hood just saying the I6 generates a lot of underhood heat

Depending on mileage on said parts you could be experiencing a sticking thermostat but you would most likely see temp rises when not towing inspect radiator hoses to ensure no minor kinks restricting coolant flow also squeeze upper radiator hose when running at full operating temp (hose will be hot be careful) you should feel pressure from the coolant flow inside of hose you could have a worn but not bad water pump not pushing enough coolant when the motor is "under load" but it's unlikely you could pull the thermostat and drive without to see if you still experience overheating conditions with constant max flow

These are the areas I would look into first to see if it's something simple or more involved hope this helps

PeterB

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Subscribed for the education.

Welcome to the forum Lisek. God luck mo.

PeterB.

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dave1123

Removing the thermostat is NOT a good idea. It allows coolant to flow thru the radiator too fast to exchange it's heat to the air. Ask anyone who's done any circle-track racing how it's worked for them. They have to run a restricter in the upper radiator hose to SLOW DOWN the flow.

Your best bet to keep it cool is to reduce the load on the cooling system, as in not using the A/C, going slower in a lower gear, and stopping to let it cool when it overheats. A larger radiator would help, but I don't think there is one available that will fit. Larger spacing between the A/C condenser and the radiator might help by allowing more air to bypass it. A larger aux trans cooler would help also and not mounted in front of the radiator. I've seen long, thin coolers mounted on trucks underneath the radiator.

More airflow also helps in the way of hood louvers and fender vents. I've also seen the rear edge of the hood lifted on hinge spacers for added cooling. This works, but any oil leaks wind up on the windshield.

All in all, I think not running the A/C would help the most. Towing 3000 lbs with a 4.0 is putting quite a load on it and long uphill pulls are the worst.