What the hell kind of roads are you driving on that you constantly scrape the middle of the bottom of the KJ? Must be some seriously deep ruts in that two-track.
Depending on the source, ground clearance for my '03, for example, range from 7.9" minimum, up to 8.9 inches.
Length 174.4 "
Body width 71.6 "
Body height 70.2 "
Wheelbase 104.3 "
Ground clearance 8.9 "
Curb 4,070 Lbs.
Gross weight 5,600 Lbs.
From 2003 Jeep Liberty Renegade 4WD - 4x4Review Off Road Magazine:
They state 9.6 for an 03 Renegade.. but I'm not sure I'd believe that. Realistically, with non-sagged suspension, the KJ should be at about 8.0" or just above.
The ruts weren't that deep, and I was surprised that I heard gravel sliding on the underside because I thought the KJ clearance was supposed to be good.
My 9-year old KJ had about 90k miles driving on it with another 90k miles km being towed behind our motorhome. Everything (shocks, springs, etc.) was the original. Is it possible that the suspension was sagging. When it was in for service, I asked the tech about the springs/shocks. He inspected and said they were fine. I found that hard to believe that the shocks were still good after all of that driving and towing. Anyway, maybe that's why I was dragging?