This '98 Grand Takes on Trails With Surgical Precision
For many of us, we spend the majority of our lives searching and building what we consider our ultimate off-road machine. Over the past few years, Dr. Stan Jack of Thornton, Colorado, has taken a '76 Jeep Grand Wagoneer, a '95 Grand Cherokee, and now a '98 Jeep Grand Cherokee ZJ and turned them all into his personal outdoor stress relievers. As a physician, what better way to spend your weekends away from emergency pagers and frantic ambulance drivers? We were fortunate enough to spend a little time riding along with Stan in Moab, Utah, seeing just how much tension we could release through the endless canyon trails.
The Suspension System
One of the first things we noticed riding shotgun in Stan's ZJ was how smooth it flowed over the rough terrain below us. Rock after rock, the suspension and tires continued to prove how purposefully this rig was built to handle whatever was thrown at it. Through years of trial and error with previous vehicles, Stan turned to Kevin's Off-Road of Phoenix to install the company's own 7-inch Long-Arm Kit to help achieve all the articulation and ground clearance needed. This system also uses a Kevin's Off-Road adjustable track bar, made from 0.156-wall, 1.25-inch-od tube; ultra-thick bushings; and Grade 8 hardware. You will also find Pro Comp MX6 shocks on the front of his ZJ and Doetsch Tech shocks soaking up hits in the rear. An Addco Heavy Duty Sway Bar has also been installed to keep the Jeep in line, as well as adjustable coil spacers both front and rear. For dependable traction, a complete set of 35x12.5R15 Goodyear MT/R tires was added on top of 15x8-inch Eagle Alloy wheels with 3.75 inches of backspacing.
Aside from height and big rubber, you won't get very far being pushed by a gutless engine. This '98 Grand is powered by a 5.2L V-8, meaning less force is needed to be applied with the driver's right foot. Soon after the purchase of Stan's ZJ, he installed a K&N FIPK (Fuel Injection Performance Kit) and a Nick Kolak Exhaust System, which combined not only increased his ponies but also brought the roar of his V-8 engine to life. This exhaust system consists of Mike Leach headers, a Flowmaster muffler, and a Car Sound catalytic converter with 3-inch piping. Also added was a Mopar Performance computer that when installed allowed higher rpm between gear shifting through the automatic transmission. An Optima Red Top battery was installed to keep the vehicle starting properly.
With all of the suspension, tires, and power now added to Stan's ZJ, the next logical step would be to get into the front and rear axles. For the rear, a popular Ford 8.8-inch was his obvious choice, especially with the abundant amount of modifications, gearsets, and lockers available. To help offset the 35-inch tires, a set of 4.88 ratio Yukon gears was added from Randy's Ring & Pinion. Locking the rear axle is a Detroit Automatic Locker. The OEM Dana 30 was removed and a much stronger Dana 30 HP (high pinion) was installed. The U-joints were also replaced with Wrangler 297 U-joints and axles. A cable-operated OX Locker was installed to put Stan's mind at ease when engaging on the trail. OX's 1/4-inch steel provides excellent gearset protection. Now that both front and rear axles were replaced, the NP249 transfer case had to go. Stan chose a NP231 transfer case with slip-yoke eliminator, allowing shifting through 2WD, 4WD, Neutral, and 4WD Low settings.