Rubicon Express Control Arm Drop Brackets
After completing the RE6130 4.5" lift I experienced some excessive Death Wobble issues. With any lift that changes the geometry of the front suspension, I always recommend getting an alignment afterward. However, even with the alignment I still had a wickedly unsettling shimmy in the front end when I hit bumps in the roads at certain speeds. Additionally, with my 96 Cherokee at 4.5Ē, this meant that every time I hit a bump, the force of the bump pushed up into the control arm and into the frame before the sidewall if the tire deformed enough to climb over the bump. On the trail this can be rough, but on the highway the constant jarring makes for a really rough ride, and itís not very forgiving on the vehicle either.
The basic premise of the Drop Brackets really is a simple one. The Brackets fit into the stock control arm pockets and relocate the mounting points four inches lower. There are reinforcing plates that help prevent twisting, and use hard ABS spacers to take up the gaps left by the old control arms. Since the Drop Brackets lower the frame-side of the control arms to an almost stock geometry, the ride is incredibly better, and because the arms are now starting out in a static (flat) position they are able to droop farther without binding...this is also very good.
You can demonstrate this for yourself using your arm. Stretch your arm out in front of you with your hand in a fist, palm down. Imagine your fist is the solid front axle, and as you move it across in front of you, your fist has to travel over obstacles in the way. With your arm relatively flat, your hand (the axle) will move up and over obstacles easily. If you raise your elbow a few inches, obstacles impact your fist before you can climb them. Dropping your elbow is the goal of Drop Brackets.
RE9900 and RE9905 Installation
I started installation on the driver's side and thought I ran into a problem when trying to set the upper control arm (UCA) in place. As you can see, there was quite a bit of a gap between the UCA bushing and the new sidepieces for that arm. Trying to fit all the bolts in place for the UCA and the lower control arm (LCA) was a bit tight, making me wonder if my LCA pocket might be warped to the passenger side...
It turns out that the gap is just fine. When everything gets tightened up the gap closes tremendously. This is evidence that it's VERY important to have all the bolts and holes in place before tightening anything.
Failure to follow this step could easily result in bolts that won't fit
Once you realize where all the parts go, installation is very straightforward. Having assisted on a couple installs previously, Iíve noticed that it's much easier to complete this installation on a fresh Cherokee. Unfortunately, the control arm pockets on the Cherokee are made of stamped sheetmetal, and ones that have seen a lot of 'wheeling often have loosened up a bit. This just makes installation that much tougher. Follow the instructions on RE's page to make sure you have everything in place before tightening anything down. This includes bolting up the RE9905 Braces if you are installing those as well.
When I originally ordered my RE6130 lift I upgraded to adjustable lower control arms, and that decision paid off nicely once I installed the Drop Brackets. The lower position meant the arms had to be shorter, so if the brackets are going on a previously-lifted Cherokee, youíll probably need new lower and possibly even upper control arms depending on the height. I have previously published a chart showing typical control arm lengths, but feedback from other Jeepers indicates some of those measurements need review. Iíll update that and repost it if I get more info.
Note on the RE9905 Braces
Use a floor jack to support the crossmember and remove one side at a time. Slide the Brace in between the frame and crossmember, install the new M10 bolts to hold it in place, and repeat for the other side. The bolts are an M10 (metric) with 1.50 pitch. Mine are overly long at 50mm but the excess length is no problem since they extend up into the frame void.
Side view of the installed Brace
Because I had previously installed (and removed) a t-case drop on Stinky, I didn't have to fight with replacing the studs. On stock Cherokees there are two bolts and two studs that hold the crossmember in place and often these are frozen with rust. The bolts are easy to remove, but folks seem to have a big problem pulling the studs. Hit that link for ideas on easy removal.
The braces donít always fit flush to the framerails, so donít be surprised if they start to deform when you tighten the four bolts on the back of the Drop Bracket itself. Once the front bolts are tight, you can tighten the crossmember bolts. I found that in many cases, tightening one set of bolts also helped loosen others, so it pays off to go over the bolts several times to make sure they are all torqued correctly.
Installed shot of the Drop Brackets and Braces
The change was amazing. After getting all the parts in place and tightening them down, I took the Jeep for a drive around the block and while it didnít feel entirely like stock, it was certainly an improved ride. There are some detractors who will tell you that the Drop Brackets reduce ground clearance and will hang the Jeep up. Looking at it, I donít see it that way at all. The LCAs are tucked in near the tires, and the braces angle back toward the crossmember so if you set them on a rock you should slide off. When driving off-road you want to place your tire on the high spot anyway instead of straddling rocks so the control arms, Drop Brackets and Braces will be away from the rocks. The only change I want to make to the stock design will be to cut a portion off the rear of the Drop Bracket behind the LCA bolt to reduce the potential for that section dragging. Look at the top picture in this writeup to get an idea of where I plan to cut.
Thatís it Ė although initially very complex-looking, the pieces come together nicely to enhance your Cherokee. Again, because they relocate the control arms approximately four inches lower, they arenít recommended for use with a lift of less than four inches.
How long should the Control Arms be??
This table is based on figures from this chart and includes Rough Country measurements from their installation instructions.