fritz_monroe, I myself have been looking at getting the "engine driven" fan. It mounts to the water pump pully, behind the radiator. Currently your jeep only has an electric fan, which is fine for towing, but is not always on. What I like about the Mechanical fan is its always pulling "some" air, no matter if its engaged or not. Which will keep the ****** cooler, ac working better, and engine cooler when sitting in traffic. This is when the ****** gets really hot b/c the electric fan doesnt stay on all the time, it comes on for awhile, then shuts back off. From the dealer, these things go for alot. Something like $250 for the clutch, and $150 for the fan. I found them much cheaper on the internet. I do believe this is a dealer install only part b/c you must have some kind of special tool to install it. Do not buy it from them. Ive check auto parts stores and everything and no one else has it but mopar. Heres where i found it for cheap.
http://www.moparsupercenter.com/
Go to Liberty, whatever year you have, miscellaneous, Transmission coolers&engine cooling upgrade. This comes as a kit from mopar, its &280 from the dealer, $252 on that site.
I believe it comes with the ****** cooler also, but its still cheaper.
Here it is from mopar.
http://www.justforjeeps.com/trcoandencou.html
Hope I helped!