1997-2006 Jeep TJ J-Spec Short-Arm Kit - Four Wheeler Magazine

1997-2006 Jeep TJ J-Spec Short-Arm Kit - Ready To Rock 1997 Jeep Tj Suspension front Drivers Side Photo 9724946 With as little as one day in the shop, our donor '97 TJ took on a whole new personality.

Plagued by bare-bones interiors and what many consider a bouncy ride character, Jeep Wranglers built between 1997 and 2006 often delight those of us with an eye towards the outdoors. Their nimble size, along with an arsenal of trail-proven attributes, make any TJ a trustworthy 4x4 right out of the box. And it's for this reason why so many enthusiasts begin buildups with them. Most popular amongst hard-core Jeepers are the smooth-riding long-arm suspension systems.

While long-arm conversions may seem like all the rage these days, they also have a few inherent drawbacks. For instance, installation time usually takes more than double that of a typical short-arm kit. Also, once you cut off all the unnecessary OE parts, a long-arm kit is often irreversible, or at the very least extremely difficult to return to stock. Not to mention the added expense associated with more complex kits. On the flip side, short-arm systems do not require a change in factory pivot points, and while most short-arm kits retain the factory-like ride mentioned earlier, they do offer greater simplicity while effectively achieving the end-all goal: Accommodating larger tires and improving flex.

We recently came across the new J-Spec short-arm kit from JKS Manufacturing. A closer look revealed quite a few innovations worth mentioning. So we procured a Stage 4 system and promptly secured use of a donor TJ to perform a six-month evaluation. The installation was a breeze compared to the typical long-arm kit, and our capable friends at Overkill Jeep Fabrication in Campbell, California, made quick work of it in just one short day. Now read on and see what makes the J-Spec suspension system ready to rock.

PhotosView Slideshow 1. The J-Spec suspension is available in coordinated stages to suit your needs and budget. To obtain the greatest benefits, we opted for the complete Stage 4 kit, which consists of new coil springs, shocks, performance shock mounts, front sway-bar disconnects, rear sway-bar end links, adjustable track bars with rear relocation bracket, rear shock extensions, upper and lower control arms, extended front brake lines, and a tailshaft conversion kit for the transfer case with CV driveshaft. 2. The Stage 4 system includes these massive upper and lower adjustable control arms. Each end twists independently and friction-free to allow big improvements in flex. Another cool feature is that each is greasable for long-lasting noise-free operation. A vulcanized rubber bushing isolates road vibrations at each end. Although they may appear to be similar to other control arms on the surface, what really distinguishes JKS arms are the features you can't see. For instance, ultrafine adjustment threads are far stronger than common coarse-thread designs. A slippery brass support bearing eliminates wear caused by leverage, and a spring-loaded seal keeps the lubricant contained and free of contamination. According to JKS, the end result is an extremely reliable design that outlasts anything else on the market. 3. The adjustable bumpstop spacers from JKS consist of three billet-aluminum interlocking pucks at each corner. We like these because they let you dial in bump clearance for different applications. A total of six unique links are possible depending on how the spacers are assembled. Very clever! 4. As the original pioneer of sway-bar quick disconnects for Jeeps, it's no surprise that the supplied JKS Quicker Disconnects are so well designed. Each end uses a spherical urethane bushing to prevent suspension bind while cornering. This allows the springs and shocks to work in harmony with the antisway bar absent of preload forces found in other typical rubber-bushing-style end links. This little detail improves on-road feel while also making the disconnect/reconnect process much easier for the end user. 5. Another aspect of the J-Spec system we liked is the custom-tuned Bilstein piggyback shock absorbers. JKS partnered with Bilstein to fine-tune these 5150-Series shocks for a perfect balance of on-road stability and rough-terrain damping. The bar-pin eliminators shown here are the cat's meow because they are super-easy to install, and much stronger than the factory stamped type. Additionally, they compress the bushing sides to eliminate noise and premature wear caused by distortion. 6. The J-Spec system is designed to raise the vehicle 4 inches over stock. Here you can see the difference between the stock rear springs and the new longer JKS units. JKS coil springs are developed specifically for the weight of six-cylinder applications and vehicles that carry heavier loads, such as tools and gear normally needed by the serious off-pavement enthusiast. PhotosView Slideshow 7. JKS also offers a slip-yoke eliminator conversion for the stock TJ transfer case. This setup converts the rear driveshaft to the more preferable fixed-yoke-type output. The output shaft shown here must be installed inside the factory transfer case. To do this, the case must be removed from the vehicle and each case half must be separated on a work bench. Once the original shaft is removed, the new shaft can be installed and the case halves can be put back together. This modification improves transfer-case life and allows for a much stronger slip-style rear driveshaft. 8. The complete J-Spec Stage 4 system also includes a new slip-style rear driveshaft from Tom Wood's. It features both heavier-duty 1350 U-joints and a high-angle CV joint. This represents a 50 percent improvement in strength over the factory setup. This arrangement also corrects driveline geometry, resulting in smoother operation and a longer life. 9. While Jeff buttoned up the transfer case, his lead mechanic, Scott Tashiro, installed the new front coil springs and shocks. The shocks, together with the specially designed coil springs, are truly what makes up the heart of the J-Spec system. Bilstein shocks are purebred performers, and when specifically valved for the TJ chassis, it doesn't get much better. 10. Prior to installing the new track bar, Jeff applied a coating of antiseize to the exposed threads. Little steps like these save big headaches later on. Although it's unlikely that the owner of our donor Jeep will ever want to adjust this track bar, he may want to take advantage of their precise adjustment capability, and thanks to the antiseize, it should be a very simple process. 11. This shot shows the driver-side lower control arm after it was installed in the vehicle. The zinc-coated end is mounted to the axle to allow full range of motion as the suspension extends. Vibration-absorbing rubber bushings eliminate the harshness usually associated with less-expensive polyurethane bushings. 12. With any CV driveshaft installation, it is necessary to rotate the rear axlehousing to optimize the pinion angle. As a result, interference can occur between the shock absorbers and axlehousing. To cure this, JKS provides these powdercoated relocation brackets to improve shock angle and clearance. 1997 Jeep Tj Suspension steering Photo 9724970

Because our donor Jeep had a slightly bent tie rod, we decided it was a good idea to upgrade the stock steering while we had it up on a lift. We chose the third-generation U-Turn kit from Off-Road Only. We like this particular kit because it was designed to correct steering geometry, thus eliminating the "dead spot" commonly associated with lifted TJs. The system is a crossover design and is much beefier than the stock setup. Noticeable improvements in the overall crispness were another result. The kit features a 4130 chromoly drag link and tie rod for ultimate durability. Also included is a trick steering stabilizer using rod-end-style joints, which eliminate steering preload commonly found on stabilizers with rubber bushings. This kit is a 100-percent bolt-on for all TJ Dana 30/44 front axles with or without ABS sensors. We loved the feel of this kit in all scenarios of driving.

PhotosView Slideshow 13. Here you can see how the new rear track-bar relocation bracket mounts to the factory track-bar bracket. We like the way JKS designed this part because it includes a zinc-coated crushproof sleeve inside the factory bracketry as well as a second bolt to help distribute forces further down on the OE bracket. Also notice the way the bracket relocates the track bar up and closer to the centerline of the axlehousing; this assists in correctly aligning the track bar once the axle has been rotated to accommodate the new CV driveshaft. This part transmits a ton of lateral force to keep the rear axle located under the Jeep. JKS knows this and designed a system that won't let you down. 14. This shot shows the new extended stainless steel braided brake lines supplied with the J-Spec system. These are about as nice as brake lines get. In addition to being made from a much stronger braided material, they feature a protective red sleeve designed to provide "witness marks" in case something accidentally comes in contact with the lines. This helps you troubleshoot clearance issues as well as preserve the good looks of the stainless steel. With these lines, you can expect improved braking performance and pedal response. 15. We chose a smooth-riding set of Goodyear MT/R tires for this project. Our good friend Tom Lonardo at Goodyear's Los Gatos, California, store always takes care of his customers, and in our case there was no exception. Tom had our new 32-inch tires mounted and balanced in a little over two hours. The OE Jeep Rubicon wheels were provided by the Jeep's owner. Here you can see Overkill's apprentice fabricator Corey Allen muscling one of the new tires in place.

Our initial testdrive revealed the J-Spec front springs were a little firm on our four-banger Jeep. We anticipated this because JKS designed the coils for the heavier six-cylinder engine. To compensate for the weight difference (and to improve the Jeep's trail functions), we installed an ARB front winch bumper and a Ramsey 8,000-pound electric winch. These additions increased the weight over the front springs, proving to be the perfect solution. Once installed, the Jeep felt perfectly balanced and the testing continued.

1997 Jeep Tj Suspension before Photo 9724985 1997 Jeep Tj Suspension after Photo 9724991

Wrapping up our six-month evaluation over a variety of different terrains, we had nothing but good things to say about the J-Spec Suspension system and the U-Turn steering upgrade. The Jeep improved big-time on the road and in the dirt, in both ride quality and articulation. This assured us that the J-Spec system was the real deal. It became obvious just how much all those little extra features contribute to the system's overall performance. This is one of the those times when the expression "the whole is greater than the sum of its parts" certainly applies. Everything from washboard to boulders confirmed our suspicions that JKS really did their homework before releasing this new system. After several thousand highway miles, we didn't hear any of the typical squeaks and rattles found with other less-expensive kits we've tested. The ride seemed to get even better as the springs broke in. The slightly larger tires had only a minimal effect on power and fuel consumption. The owner does plan to swap in a stroked 4.0L soon. Once he does, we suspect a set of 33s will follow suit. Lucky for him, the 4 additional inches of clearance will accommodate these without issue. For now, however, this Jeep is ready to rock.