ZJ Steering Box Braces

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http://kevinsoffroad.com/jeep/jeep-grand-cherokee-zj/zj-steering-gearbox-brace/

How long has it been since you've checked your three steering gear bolts?  Have you noticed looseness in your steering? Do they come loose often? If so, it's probably because you've added quite a bit of force to the system by adding taller and wider tires.  Let me impress upon you how important it is to KNOW that they're they tight!  See, every action has an equal and opposite reaction.  You learned that in High School Physics, right?  Anyway, when you turn the steering wheel to the right, the pitman arm forces the tie-rod to the right, pushing the front of the wheel rightward so you can turn the Jeep.  It also pushes the driver's side frame rail leftward at the same time which is where the steering box is mounted.  If you had a skinny little 28" tire on there, the steering gear has no problem overcoming the friction of the tire's contact patch on the pavement because it's only like 16 square inches of area at correct inflation.  By way of comparison, a 31" tire is nearly THREE TIMES that amount of area at the correct inflation.  (when volume of tire increases, less pressure is needed *OR WANTED*, so the tire lays on the pavement more.  Proper inflation for a 31" tire is probably around 24psi in the front and less on the rear on most ZJs.  Use the chalk-method to insure that your tires are properly inflated and not over-inflated).  Have any idea what a 35" tire's contact patch looks like?  It's probably three times a 31" tire!

Secondly, have you noticed how many bolts are holding the steering box to the frame?  Exactly 3.  And, they are all at the top, not down at the bottom where you need them to brace the forces of the larger contact patch, not to mention pushing up against a rock or tree when you are offroad.  It's essentially a hydraulic-assisted lever with a bracket on only one end to brace it.  How long until it fails?  How tight are your bolts?  Once they are loose, the box will work back and forth under the Jeep until it either shears off one of the three bolts or rips off one of the ears on the box (or both, like what happened to me on Pritchett Canyon in Moab).

How strong is is?  Well, strong enough to hold my steering box in position tightly while I broke the steering gear sector shaft in two.  The photo below to the upper right is of my drag link dangling after the pitman arm sheared off the steering box sector shaft.  You can still see the nut under the pitman arm...it sheared right above the pitman arm.  When I went to remove the bolts on the steering gear box that go through the frame, I expected to find them loose again, like they were before I installed this brace in 2005.  Huh uh...those babies were TIGHT.  That box was not moving at ALL.  The 1-1/4" thick, hardened sector shaft sheared from the stress of 37" tires and a front locker, but the box was held straight and true with the box brace in position.  If that's not a true test of how much force the steering box brace takes off of the box's frame mounts, I'm not sure what is.

So, you can see why it's important to have a steering brace for your steering box.  Without further adieu, allow me to introduce our steering box brace for the ZJ, which bolts in on both sides of the front frame rail to the factory skid plate and sway bar mounting holes and clamps solidly to the steering box, keeping it from moving around on the lower end where there is no support.  It'll increase your steering response, will keep you from breaking tabs off of the steering gear like I did, and will keep the factory gear bolts tighter on the frame.  Comes powdercoated to resist the elements and includes all the hardware you need to bolt it right in.  No cutting, welding, modifying necessary.  You can even re-use the worthless front factory skid if you elect to do so, but you may need to modify the rear tabs ever so slightly so that they don't come inboard as far.  No biggie.  It'll be obvious what to do when you get it under there.  Personally, there is nothing that the front skid really protects, once you're lifted, so you may just ditch it and be done with it.  That's what I did.