Initially, I had been looking for a solution in the department of swapping my stock 4255 rear spring and the spacer my lift came with, for just a taller/stiffer spring. I had two reasons for this; one being the obvious of eliminating the spacer, and the other being getting more load capacity in the rear since my 4255 rear springs are weak as balls and sag horribly when i'm pulling my boat or have people in the back seats.

With that said, I did the research and spoke to Rancho and a few other manufacturers, and it seems in the rear the spacer is just fine for the amount of lift I have. So I switched gears and decided to find a higher rate spring for the rear in order to accommodate heavier payloads. After speaking with a friend, I was able to locate some 4458 take offs from a JKU. Price? Free, just paid shipping. That was the best part.

One of the concerns I had was gaining too much more lift because of some results I noted from other jeepers, doing the same thing. I obviously didn't want to open another can of worms, and I also didn't want too much of a rake. But after doing a quick swap last night, it turned out great. It did bring the back end up a little. Before we stuck the spring in, we put the my stock 4255 beside the 4458 and you could see just about a 1/4" difference in height. So not a big deal there. And you could also tell the spring was a bit heavier and stiffer, so we figured a tad bit more gain from that. Once installed and on the pad, I gained not quite 3/4" in the rear, which gave it a slight rake. I don't mind that so much, since the whole idea was for load capacity, so it serves a purpose. I'll have a full load on the trails this weekend, so we will see how it handle weight in the back then in the form of two people, coolers, air, etc...

I saw one thread that mentioned for every number you go up in spring rate, you gain 1/4 of an inch. Based on my results, I can concur that logic and would say that's a legit expectation. So those of you wanting a really cheap lift, and there is a shop locally that does installs, you might be able to find some take offs cheap cheap or free, and get a proper spring lift for your jeep. Here is a pick of mine in the rear after installation of a 4458 spring under the Rancho 1.75" spacer on my JK.

 

how hard is the swap? I have to do the same to my Jeep next week, but I'm adding a 2" lift kit to my stock ride. It does have the spacers.

I guess I need to buy a floor jack and stands too and the spring clamps. I'm stoked that they are ranchos.

 

It's not hard. The lift itself will take you about 4 hours if you have the right tools and someone to help you. I would recommend you do one side at the time, not both. It's much easier. You'll need at least two jacks, one for the axle, and one to keep the frame of your jeep up while you lower your axle. Tall jack stands are needed, or you can build the base up with bricks or wood. Ratcheting metric wrenches, drill, ratchet set, knife to trim a little plastic around top of front shock, and other basic tools. While you are doing the lift, go ahead and swap your stock springs for the heavier ones, that's kind of a no brainer.