XJ Bullet Proof Steering

Introduction

After several years of hard use the stock steering on my XJ had seen better days. The dust boots on the rod ends had vanished long ago and regardless of how much grease was pumped into them they were just too worn to hold any kind of alignment. To make matters worse I had a nice big bend in the factory tie rod that made making adjustments even more of a guessing game. I am not a big fan of the stock "inverted Y" setup even in perfect condition due to the fact that it needs to be aligned every time the suspension height is altered. After multiple coil spring and spacer swaps I was tired of constantly needing an alignment so I knew I needed something with a one piece tie rod that spanned from knuckle to knuckle. This way all I would need to change after altering the ride height would be the steering wheel position. The solution to my problems was to go with a Bullet Proof setup from Performance Unlimited.

The Performance Unlimited system uses a tie rod which spans from knuckle to knuckle and a drag link which stretches from the pitman arm to the passenger side knuckle. This kit can be configured in two ways, one of which places both the tie rod and drag link over the knuckle, and another which puts the tie rod below and the drag link above the knuckle. When changing to this type of setup on a Cherokee or track bar equipped vehicle it is important that the drag link and track bar are at similar operating angles. If they move in different arcs through the suspensions range of motion then a phenomenon known a "bump steer" will occur. Basically this is when the steering wheel will move left or right every time you hit a bump or pothole and often makes the steering feel like it has a mind of its own. This sharp jerking can also introduce "death wobble", which is when the wheels shake violently back and forth without any way to stop it. Anyone who has experienced this knows how scary it can be when it happens while traveling down the road at highway speeds. Both of these problems can be amplified by poor alignment, worn steering stabilizer, out of balance tires, and a host of other issues so make sure that your Jeep is in good repair before attempting to change the factory steering setup.

Product

The Bullet Proof system comes with pre-cut tie rod and drag link tubing, 4 heim joints (2 RH thread, 2 LH thread), 4 jam nuts, 3 sets of F911 bolts and castle nuts, and all the required spacers needed for the installation. You will need to fabricate a bracket for the steering dampener as well as extensions for the sway bar axle brackets. They offer three sizes of heat-treated 1026 DOM tubing depending on the degree of strength you are after. For most applications the Trail Proof (1.125" OD, .22" wall) is more than adequate, but if you have to have something stronger then they offer a Race Proof (1.375" OD, .375" wall) and the ultra beefy Rock Proof (1.5" OD, .5" wall). Going any larger than the Trail Proof size on a Dana 30 axle is not necessary because the weak link will just be moved to another component and will not provide any additional strength.

Also, the thicker tubing will create more clearance issues and can result in a diminished turning radius. Each bar comes with a grayish-silver powdercoat finish as well as milled slots at each end that allow for easy adjustments. The kit uses HD 3/4" heims that are lined with a Teflon/Kevlar race and are said to be self-lubricating and require no maintanance. The entire system is held together with aerospace quality F911 nuts and bolts which are rated at a Grade 9 and can withstand a torque load of 530 ft/lbs!

This is not a one-size fits all kit due to various lift heights so it is necessary to make a few measurements before placing your order.

The two key dimensions that Performance Unlimited needs are the distance from knuckle to knuckle (center of rod end holes) and the distance from knuckle to pitman arm. They try to make the tubing as long as possible to maximize the amount of threads that will be engaged on the heims, which also means that it can still be adjusted to get you off the trail if by some chance the tubing ever bends. Another great feature of the material they use for the tubing is that is designed to flex up to 4" if impacted and still return to its original shape without any permanent damage.

Tools Required

Tape Measure
1/2" Ratchet w/ assorted sockets (1 1/8" for F911 bolts)
Electric Drill
5/8" & 3/4" Countersinks or Drill Bits
15/16" Wrench
Vise Grips or large Crescent Wrench
Anti-Seize Compound
5/16" Cobalt Drill Bit
5/16" Cotter Pins (3x)
Cutting Oil
Angle Grinder w/cutoff wheel or hacksaw
Welder (required for attaching new sway bar brackets)

Installation

The instruction that Performance Unlimited supplied with the kit were very detailed and should be enough to guide you through the entire process, but for those who want to see what is involved here is the process I went through. The first thing I did after removing the tires and supporting the front end on jack stands was to measure the exact distance for the new tie rod. The quickest way to measure this was to use the lines on the end of the steering arms that are part of the knuckle casting. These raised lines are perfectly in-line with the center of the holes for the rod ends so it gives a fairly accurate measurement as a starting point for the new tie rod. Next, I disconnected the sway bar end links and steering stabilizer. Don't worry about trying to pry the stabilizer stud out of the drag link because you won't be reusing it anyway. Then I used a separator to remove the stock rod ends and steering linkage. It is possible to use a hammer to pound the rod ends out, but getting to the one in the pitman arm can be difficult due to the limited amount of space. Save yourself some time and irritation and go rent or buy one of these tools from your local auto parts store. Once all the stock linkage was removed I began opening up the holes in the knuckles and pitman arm to accept the new 3/4" bolts.

The easiest way I found to drill these 3/4" holes was to use countersink bits instead of regular split point drill bits. The multiple cutting flutes on the countersink bits chewed through the castings very easily whereas the drill bits tended to smoke and bounce around a lot without making a whole lot of progress. Start out with a 5/8" bit and then finish the hole with a 3/4" making sure to go slow and use lots of cutting oil. Also make sure that you wear eye protection to avoid hot metal shavings from getting in your eyes, trust me you will get them all over you when you start drilling the pitman arm. If you really wanted to you could remove the pitman arm prior to drilling, but it isn't necessary. Once all the holes were drilled I used an angle grinder (w/ cutoff wheel) and removed the stock sway bar end link mounts. I cut just enough off of the mounts to allow for clearance with the new linkage while still maintaining enough material to weld the new brackets to. If you are running a set of adjustable end links (i.e. JKS Gen. II) then you can probably get away with only modifying the passenger side bracket and leaving the drivers side alone. However, if you have fixed length end links then you will have to fabricate identical brackets for both sides to maintain use of the sway bar. I would suggest making these brackets out of steel that is thicker than 1/4" due to the large amount of stress being placed on them and their tendency to bend. I also wouldn't suggest bolting them on because no matter how tight you get them in your driveway they will undoubtedly loosen up once you hit the road. As you can see from the picture the mounts just don't hold up well when bolted on and made out of 1/4" material. With the sway bar mounts removed I then began bolting up the new linkage.

When installing the heims into the tubing make sure that you apply anti-seize to the threads so that it doesn't rust in place and prevent further adjustments. Also, remember that one end of the tubing has a left hand thread and the other has a right hand thread so the length can simply be adjusted by just loosening the jam nuts and turning the tube. Check your tie rod length prior to bolting it onto the vehicle because I had a problem with both my pieces of tubing being too long.

I ran out of adjustment before the links were the right size and ended up having to trim about an 1/8" off each end. While I wasn't too thrilled about having to cut into the nice powdercoat finish this was the only problem I had with the kit and I think it might have been due to my slightly inaccurate measurements that I gave when I ordered the parts. With the links set to the right length it is then just a matter of bolting them up with the supplied spacers and cranking down on the huge 3/4" bolts. Don't worry about over torqueing the bolts because they can withstand almost any force you can put on them. If the bolts are too long they can be trimmed with a cutoff wheel and a grinder, but make sure that you leave enough thread to fully engage the castle nut. Once all the linkage was bolted up I used a 5/16" Cobalt bit to drill holes in the bolts for the cotter pins to keep the castle nuts from backing off. If you don't use a Cobalt bit you will end up destroying several bits and will probably never get through the hardened bolt. The last step of installation was to bolt up the steering dampener using the new bracket that I fabricated using 3/8" plate and two 1.5" U-bolts. The only thing left to do is to get an alignment and your done.

Conclusion

During my initial testing of the new setup I was a little concerned about the amount of bump steer I was having, but once I had the sway bars securely hooked up and the stabilizer mount in place it became very manageable. There is still a small amount that occurs when I hit big dips in the highway but for the most part the steering is very tight and tracks straight on the street.

I was so used to the extra slop in the stock setup that it took some getting used to the returned firm feeling of the wheel, but now I am loving it. The alignment guys were also very impressed by the ease in which they can now adjust the toe without having to mess with the inverted Y setup.

I did notice that I could not steer all the way to the stops when turning right and that was because the thicker tubing was coming in contact with the track bar bolt. It didn't take too much away from my turning radius but it is still something I would like to address is the future by moving the track bar to the top of the axle. I did end up taking my grinder to the bolt to give me just a little more clearance but it didn't improve my turning radius much. The best part about having this beefy setup is not having to worry about it. When I hit the trail I no longer have to worry about smashing and bending the stock linkage and trying to rig something up to make it home. For the serious four wheeler I would highly recommend the kit that Performance Unlimited sells. The whole project ended up costing me less than $400 and took about 5 hours to install, which includes the time required to make the sway bar and stabilizer brackets.

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Last modified Friday, 06-Sep-2002 16:39:45 CEST
by morten

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Introduction

Product

Tools Required

Installation

Conclusion