I have the 3:92 gearing. It is nice for towing, but sometimes wished I had taller gears when cruising. I receintly drove from DFW to north Georgia and back. I can't remember excatly, but got 18+ MPG on one tank. I got high 17s on the rest. Oddly enough, the 18+ was when my 16 yo dtr was driving.

 

Chemo see I have never seen the 18 mpg mark. I have the 3.55's and thebest I have ever seen was 17.5 and it was me all by myself in the truck completely empty. I was getting 15 mpg at the best when I drove from NY to NV. All of this mileage was strictly highway with cruise control on.

 

Unlike other manufacturers, DC didnot include the lower gear (3.92) as part of their tow package. My 01 has the TP and has the 3.55 gear. The TP did not include the Anti Spin (limited slip) differential either.

AConsumer GuideI have for the 03 model yearlists the following by group.

Light Duty Trailer Group:
Heated power mirrors, 7 wire harness, hitch receiver,

Heavy Duty Tow Group:
Heated power mirrors, heavy duty service group, heavy duty cooling and battery, 7 wire harness, Class 4 hitch.

The 3.92 axle ratio was a stand alone option with the exception of being included in the R/T package.

Don

 

Your right, there is alot more than hitch and wiring. 1- Synthetic gear oil in the rear diff 75/140 is required along with an aux. trans oil cooler. The factory package also included a bigger radiator,HD fan clutch, high amp alt, pwr steering cooler,and a bigger battery. Look under the hood, if you see a tranny cooler your in good shape, they were NOT standard equipment.

 

I don't think DC put the same thing on any twovehicles. My 99 came with the "tow group."Itcame with the hitch,a 7 wire harness and the plug for the brake controller, buthas no tranny cooler. Has small non heatedmirrors and as far as I can tell the standard alternator. It definately has 3:92 gears though.