Good timing! I just replaced the worn out leafs on my 2000. I did not want to go with any big lift, and when we travel the jeep is usually freighted right up with gear, kayaks, and towing a teardrop camper. 87k on it. The springs would sag so bad the axle was higher than the shackles and I had minimal tire rub clearance in the rear wells. So after lots of studying I settled on a set of heavy duty springs equivalent to the Up Country stuff, 755# rating. Got them for a good price from General Spring in Kansas City. Even shipped to me the price was competitive at $79/side and they come with the bushings installed. I just finished putting them on yesterday. Not an easy job but I bulled through it.
Next is getting an inch more lift on the front to level it out. Spacers for now but uprated springs will be the final deal. I don't wheel or mud run, just back woods roads and logging roads so I think this is a good answer.
Add a leafs on old springs, according to the guru's an NAXJA, will simply hasten the decline of the old spring back even faster. The factory did it right with that Up Country package.
Good luck with your setup! The higher rated springs are very nice to have. I personally like to have the rear of my jeep higher than the front, it allows me to load more gear without inducing negative rake. The upcountry package is definately a nice feature to have. Most people arent aware that along with higher and better springs, It comes with maximum engine cooling, a transmission cooler, a full set of skid plates ( front, tcase, gas tank) a limited slip rear differential, a set of front tow hooks,factory rear sway bar delete and either a class 3 hitch or a rear tow hook. Mine is equipped with the hitch.
I began looking into purchasing a lift kit after my freinds father sold me a set of barely used 31/10.5 BFG AT's, the tires fit and are able to take most dirt trails without rubbing. However, when the suspension has to really flex, the rear tires rub the inner fender flare. This is why I decided to buy a lift instead of replacing factory components.
Also, if my jeep is riding 1 inch over stock, will a 3 inch add a leaf result in a 4 inch lift ove a non upcountry vehicle?