Well, about it not being a powerhouse, you've got to keep in mind it's a heavy beast for it's size because it's carrying 2 live axles and a t/case with only 185 hp, BUT it's a torquey beast with it's "tractor" engine. In addition, 4th gear is overdrive for highway use so that 25% of the power is lost in order for it to run at the higher speeds. I live in upstate NY where it's rolling hills and small country roads, so my normal driving speeds tend to be around 45-50 and I keep it in 3rd gear most of the time. It's not unusual to come around a corner and come face-to-face with a loaded farm trailer pulled by a tractor! Just for your enlightenment, here's a power curve chart for the 4.0. This is for the 99-04 Grand Cherokee which had a slightly different cam than your model, but you get the picture. Notice the hp and torque output at 1800 rpm which is about 55 mph. 1500 with my gearing. You gain a lot of horsepower by dropping down a gear.