Now another lift quesiton..

A 1" BL should be enough.

Jerry

I can't see needing 4" + 2" to fit 33's on a YJ but anyway... Be careful messing around with shackles on replacement springs. I think we've had this conversation before regarding your XJ.

-Brian

I belive we did. My YJ now has 1" lift shackles on it.. Will these be re-useable when I install the kit?

Carl

Two of my buddies just finished putting these on ...one of them is riding with 32" right now and has a rediculous amount of clearance still. He could definitely do 33's and he's thinking of just adding a 2" body and going with

35's. I can't see how you couldn't fit 33's ...

You are going to have to be really careful with the alignment with longer shackles. Adding two aftermarket lifts together can be trouble. You have to start messing with shims or try and find an alignment shop with shim sets to get it back proper. Some combinations can turn into real abortions with the steering control extremely compromised. These usually turn into 'trailer queens' that have to be hauled to the trail head because they aren't safe over 40 mph.

Now as far as fitting tires, stock 31x10.5's will 'work' on the street on some YJ's without too much rub.

You are adding 4"!!!!

I only had to add 3" to have tons of room for 33x9.5's's on my CJ7, but it can take 31's with no rub.

I would sure try it without the body lift and see what happens. If you tag at full flex, you can always add a little to the bump stop height so it hits that before the tire tags.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Carl Saiyed wrote:

So I need to get stock type shackles again? I'll put the 4" kit on with the

33x 12.5's and if I rub I'll probably to a shackle reversal in the front maybe a 1" shackle in the rear? Then if I MUST, I'll go with a 1 or 2" body lift.

Carl

I 'think' by some info in another thread that that lift comes with longer shackles and shims?

If so, then if yours are the same length and 'better' quality I would just use them.

I have YJ shackles in my CJ7 (1" longer only) with stock new Jeep springs arched 2.5" and the shackles affect the steering. It won't self center well after a turn, you have to crank the wheel back to center and I have a slight rear driveshaft vibe with no load on.

Mike

Carl Saiyed wrote:

RE5515. Comes with shims, but no shackles. A friend told me something about possibly needing angle shackles because the springs are "full military wrap"?

Carl

Or is it worth it to step up to the RE5520?

Carl

Longer shackles can do nasty things. Besides tossing the steering angles off, they allow the springs to over flex. This allows the springs to 'say' flex out flat or even invert because the shackle will move 'out' making a longer anchor point as the spring compresses.

The proper shackle for the spring controls this and stops moving when the spring still has an arch left so it can't over flex.

Some springs apparently need longer shackles or they will bind up on a heavy flex or that is just a cheap way for them to sell an 'extreme' kit which is now getting into 'trailer queen' territory.

I would be very careful about mixing and matching lifts....

Mike

Carl Saiyed wrote:

Perhaps. The 5520 kit (4.5" Extreme Duty) uses a completely different spring formula tuned to 1" longer shackles. It comes with more components, but not with shocks, which RE now prefers to custom tailor to your use when you order. Mine came with the DT 3000s, which were too weak for the weight of my axles (Dynatrac D44 & D60).

From personal experience I highly recommend the 5520 kit. Several of us locally are using it with great success. The street and trail ride quality is outstanding and they flex like mad on the rocks. I've had one installed on my YJ since '02 and generally beaten the crap out of it without any issues whatsoever. It's only settled maybe 1/4" since new and provides a measured average 5 3/8" lift.

Best I can remember, the 5515 kit is actually a Pro Comp 4" lift, which RE sources from 4 Wheel Parts. Don't hold me to this, however, as that info came from Avalanche several years ago and I dont know anyone running the

5515 kit. (FWIW, Pro Comp leaft spring kits are notoriously stiff with poor flex.)

Both of the kits come with transfer case drop spacers, but really need to be installed with an SYE & CV rear driveshaft, as would any 4" lift on a YJ. Also, the 5520 kit's longer front shackles require the front end to be shimmed (or the spring pads cut & relocated) to get the caster back into spec. RE ships 2 sets of Pro Comp aluminum 2.5 degree shims with the 5520 kit, one set to be used in the rear to compensate pinion angle, the other set for the front to set the caster. I would never use or recommend aluminum shims to begin with, much less on the front axle. They crack over time & will get spit out. It's one thing for that to happen in the rear, another thing altogether should it happen up front. For the front axle on my YJ I sourced 2 degree steel shims from Poison Spyder Customs and they've worked like a charm.

Thanks, Mike and SoK66. I'll step up to the RE5520. I'll also try to upgrade to Rubicon Monotubes when I order the kit. I don't want to mix shackles, and the RE5520 comes with new shackles.

Carl

Mike, taller lift springs are longer, measured along the arch. In order to have more lift, and attach to the same mounts, the leaf is a little longer....when compressed, (flattened) they will be longer, and without the longer shackles, the spring will not be able to compress/extend as much as it needs to be.....the spring will compress to the point where the shackle is horizontal and the suspension will feel like it's bottomed out.

Paul

Mike Roma>

Rumour was, a few years ago, that the 5520 (and all the other "Extreme" kits from RE) uses National Spring (thumbs up) leafs, while the 5515 uses Pro Comp (thumbs down) leafs.

Paul

Carl Saiyed wrote:

The current 4.5" lift only comes with rear shim's. They've redesigned the front and done away with the front shim's. Give a call to Rubicon extreme and they'll fill you in. The 4.5" kit is really worth the extra $$. Awesome kit!!