I have a 2004 Laredo that has had multiple cooling issues. I had the radiator fan go out, then the radiator itself started leaking. I replaced the radiator with a new one, and the Jeep seemed to run hot more often. It would not over heat just run warm around the 210 degree mark. The seal around the thermostat started leaking a few months later, I then replaced the thermostat. Still despite all the new parts, the engine runs warm. The mechanic at my work thought that there might be air in the system causing the engine to run warm (we also checked for a head gasket leak). A year later the radiator fan went out again (cheap aftermarket from the parts store). While I had everything apart again I decided to clean the overflow tank. It was nasty. While cleaning the tank I noticed that the small outlet to the overflow hose was clogged. I went ahead and got the gunk out of that. I then decided to check the the hose itself and it was also clogged. I replaced the hose and put everything back together after flushing the engine and newer radiator. To my surprise the jeep runs very cool now. It is spring here in Kentucky and around 70 degrees during the day, the warm weather has not kicked in yet. Curious I took to the internet to find out about if the overflow tank and hose being clogged would cause over heating and found out that newer vehicles use the tank to pressurize the system. Which would make sense why I was having seals leak and the engine running warm. I am not a qualified mechanic, nor would I consider myself shade tree level. This might help you diagnose your problem. BTW, the engine temp would go up very quickly when idling, and at stop lights, then drop just as quickly at highway speeds which I think would indicate air in the system. Now, just cool all the time.

 

Your cooling system is DESIGNED to run at 210*F normal operating temperature. Anything less than that and the computer thinks it's not warmed up yet and keeps the mixture rich. In order to keep emissions low, the temp must walk the edge of the cliff of destruction called "overheating." It should use a 195*F thermostat to keep the engine temp no lower than that and use the fan(s) to keep it lower than 220*F.

The reservoir tank on your jeep is not pressurized and is used to retain expansion until the coolant cools off and is sucked back in. If the hoses are plugged the pressure can rise to the point of popping seals and blowing out radiators. If they are plugged enough to let coolant flow out but not clear enough to allow free flow back in, it will cause a vacuum in the system causing air to enter the system by bypassing pressure seals in the opposite direction than they are designed to function.

Proper maintenance of the cooling system is imperative to long engine life, especially with the 4.7 V8 with aluminum heads.

 

We can bump you up into an all aluminum 2 row. The cores are 1 3/4 thick. will give you more fluid in the unit to help cool the engine, but I must agree with Dave1123

If you need any radiator advice drop me a line

Michael