I just spent awhile emailing back and forth with Teraflex about these coil springs. So I thought I'd share my findings here.

The performance leveling coil springs are linear springs.
The spring rate is 30lbs stiffer than stock (not sure which stock spring they're referring to).
The springs are also longer with more coils.

As we all know the springs in the performance leveling kit level the stance by providing 2" of front lift and 1" of lift in the rear. But what if you don't want a level stance? Level looks great when unloaded. But as soon as you load up to hit the far away trails, your jeep starts dragging its ass.

So this is what Teraflex recommended:

To achieve a 1" lift front and rear on a 4dr hard top, run the 2dr Coil Springs in the front 1853022, and The 4dr springs in the rear 1854052.

This way, you'll have a stiffer ride with less sagging. Achieve a mild lift that won't make your stock tires look stupid. And maintain the factory rake. With such a minimal front lift, track bar, sway bar and caster issues will probably be very minimal. You also probably won't need extended sway bar links.

I'm going to install this set up on my 2014 JKUR hardtop with 17/60 springs and report back. On my Jeep's latest "Overlanding" style trip, this stock suspension was way too soft for moderate speed whoops, load carrying etc. Hopefully, this will solve those problems.

 

I have installed two of the TF performance coil kits on jku's my 2013 and my buddy's 2104 jku. I would not no put the 2 door coils up front other wise you will be lower than stock in month. I like how the coils feel on road and off road but both of us had to add spacers because they sagged so fast. On my new 2014 jkur I put Rock Krawler 1.5" triple rate coils and much better... I was running stock bumpers and so is my buddy. You will not get enough lift with 2 door coils to make it worth your while.

 

The question I would have is what is the actual spring rate of each coil?

So there are only 3 companies that make coils for a 1.5 lift?

 

I can also tell you with both the TF and the RK my castor numbers were within factory specs 3.9 and 3.7 on tf and 3.8 and 3.7 on RK
both were tall enough to run 34's but also look fine with stock size tires.

 

This is the reply I received from Teraflex regarding the spring leveling kit. I have a '14 JKUR so take that into consideration. But may help your opinion.

"Hi Stuart. Our spring leveling kit on a Rubicon will provide about an inch of lift in the front and ¼”to a ½” in the rear. The Rubicon comes with a taller spring than a standard model jeep. You will still get the leveling effect from our lift. Our springs are a slightly higher spring rate than a stock spring. Our spring provide a smooth ride while removing the mushy feeling from a stock spring. You can retain your stock shocks and tires and rims with no need for wheel spacers. The extended sway bar links we provide will work fine with the elec. Disco. This is an effective way to gain a mild lift improve handling, but still maintaining close to stock suspension geometry.
Thanks for your interest,
Doug."

 

I had that conversation with Tera Flex and I explained that rubicons and sports could have the same springs and in fact my buddies sport had higher rate springs then my rubicon. They said they were surprised and did not know that.

 

Yeah that seemed like a generalization from TF. How do those RK 1.5s compare to the TF. Any photos?

 

they are very similar in how they handle on and off road. The RK have not sagged in the front at all and a little in the back but nothing like the tf did. for the money the RK is a better deal.

 

silver one has the TF coils the white RK coils.

 

What size tires are you running in these pics?