1998 Jeep Grand Cherokee ZJ - The Adventure Grand: Part 1

    ZJ Basics

    Ali Mansour Ali MansourPhotographer, Writer

    If you’ve browsed any new car lot lately, you are probably still recovering from sticker shock. We’ve transitioned to a time where a diesel “work truck” can sell for $70,000, and a vehicle designed to have a completely removable top and doors is going for over $40,000. How is almost beyond comprehension. We’ve been in the market for a four-door SUV for a little while now. With so many new and used options, we had to sit down and craft a list of our needs and wants.

    Our goal: Build a competent ’wheeler that can be driven daily and handle cross-country treks in comfort. Also, we didn’t want to be the slug on the road, so a reasonable powerplant was high on the list. Given that many of the trails we ’wheel in the southeast are tree-lined, we quickly ruled out fullsize SUVs. The next item was price. We knew we wanted to modify the rig, so the less we spent on the initial purchase price, the more we could free up for upgrades. Ultimately, we decided on a $5,000 price cap.

    That price max took out a host of options, but unveiled a commonality -- the 1993-to-1998 Jeep Grand Cherokee ZJ. We had owned a mildly built ZJ years ago and enjoyed it immensely. The idea of building another was alluring, but it had to be the right Jeep. Your average Grand Cherokee owner probably isn’t aware of the immense build potential of the ZJ. This means, the ZJ is often driven until it’s falling apart from each end.

    While the Unitbody-construction of the Grand Cherokee can make it a bit more challenging to build, it’s not a major deterrent. With a V-8 option, multilink suspension, solid front and rear axles, and trail-friendly 105-inch wheelbase, the ZJ has the makings of a great ’wheeler right out of the box. Seating for five is also a plus if your travels include more than your significant other. And the fact that aftermarket support is as strong as it’s ever been for the ZJ makes it a logical pick.

    At first, finding one worthy of dumping any real money in seemed like a lost cause, but we gave it a shot. After a few months of searching the interweb, we stumbled across a Craigslist ad for a 1998 Jeep Grand Cherokee Limited ZJ. The listing said the Jeep only had 127,000 miles and no rust. After a few email exchanges, we got some more detailed photos, and noticed a couple oddities that had us intrigued. For starters, it was equipped with a 5.2-liter V-8, which was a bonus, but the transfer case shift bezel clearly showed the selection range for a NP242 transfer case. Since the fulltime NP249 is generally standard issue with the V-8 models, we were curious about the unique pairing. The idea of two-wheel-drive option in a V-8 Jeep Grand Cherokee sounded like a good time to us. The next item we were perplexed about was the instrument panel. Everything appeared normal, except the temp and oil pressure gauges, which were were metric, not imperial.

    At this point, our curiosity had been peaked. So, we set off to uncover the mystery of this ZJ. Once we arrived, it was clear it was a well-kept Jeep. The white paint had been professionally re-done, with no clearly visible rust or damage, and the inside was in decent shape for a vehicle of its age. Crawling underneath, we spotted the NP242 transfer case, which the owner explained had already been swapped in when he purchased the Jeep. A test drive revealed a few worn parts in the suspension, but nothing to cause great concern.

    After a little negotiation, we settled on a price that made us both happy. This brings us up to date with the Jeep you see before you. Since we plan to do more backcountry exploration with the ZJ than hardcore rockcrawling, we thought appropriate to dub it the Adventure Grand.

    Over the course of the next few months, we will be transforming our once luxo-SUV into a formidable ’wheeler. This month, we are diving into the basics with help from our local 4Wheel Parts in Raleigh, North Carolina. A quick shakedown and tune-up is always a must when purchasing a used rig, especially one with over 100,000 miles.

    Be sure to check back next month for part II of the Adventure Grand build series. Also, don’t forget to visit our supersite www.fourwheeler.com for exclusive updates and behind-the-scenes photos of the build.

    After a few days of not running, we found the stock battery was no longer viable. Since we knew the Jeep would receive extra electronic accessories, we decided to upgrade the stock battery with an Odyssey Extreme series. The 34-PC1500 Odyssey dry-cell battery offers a cold-cranking amp rating of 850. Using dry-cell technology, the battery is better suited for dealing with the rigors of off-roading and powering high-draw items like an electronic winch.

    The Grand’s 5.2-liter V-8 is rated at 220hp and 300 lb-ft of torque. That’s more than enough to power the sub 4,000-pound SUV on- and off-road with ease. If you look closely, under the air intake is the cord for the factory block heater. It leads to a single freeze plug on the water jacket. From our research, the block heater upgrade appears to be standard issue on Canadian ZJs.

    Speaking of Canadian, how about those metric gauges, eh? A quick Car Fax uncovered our ZJ originally hailed from Quebec. We could easily swap the gauges for an imperial set, but the novelty of the metric dials is worth keeping in place.

    The NP242 conversion was done rather well. Having the ability to shift between 2HI, 4-HI part-time, 4-HI, and 4-Lo, is definitely beneficial for daily driving and ’wheeling. The conversion should slightly help fuel economy as well.

    The New Process 242 retains the factory slip-shaft. We noticed a slight driveline vibration, mostly likely due to the lack of a constant velocity joint at the T-case.

    Certain Jeep Grand Cherokees were fitted with sealed-boot CVs at the front differential yoke and axleshafts. The big issue with the joint has more to do with boot failure than the joint design.

    Once the boot is ripped, it allows grease to escape and lets the elements in, which leads to rapid failure. For now, we are keeping the low-pinion Dana 30 frontend in place, but have some easy upgrades in store.

    Another item that typically comes with the V-8-equipped Jeep Grand Cherokee ZJ is the Dana 44A semi-float rear axle. While the Dana 44 part might sound familiar, it’s the A at the end that makes the rear axle unique. The A stands for aluminum -- the actual differential housing is comprised of the lightweight material. The Dana 44A can be problematic and extremely expensive to re-gear.

    A 2-inch budget boost, along with 245/75R16 BFG All-Terrains was already installed when we purchased the Jeep. We are digging the factory Rubicon TJ wheels, but have a more substantial tire and wheel package in mind.

    No matter how recently the previous owner claimed to have changed the fluids, we always go back through and change them ourselves. We like to use Royal Purple synthetic oils, mainly due to the longer lifecycle and cooling properties synthetic oils provide.

    We figured it was worth taking a look at the spark plugs to see what condition they were in. As you can see, the stock plugs had seen better days.

    Instead of swapping the plugs, we decided to give the engine a tune up with Accel. The Accel performance tune-up kit came with new plug wires with ceramic ends, distributor cap, rotor, and plugs. We also upgraded with the Accel performance coil, which required the company’s adapter.

    Some upgrades aren’t overly exciting, but absolutely necessary. The inside of the Limited ZJ is in good shape, and we plan to keep it that way. Dropping in a set of floor and cargo liners from Rugged Ridge is an inexpensive way to protect our investment, and the liners allow easy cleanup when the adventure is over.

    Having the experts at 4Wheel Parts help shake down the new-to-us rig was extremely valuable. Sometimes, it’s easy to overlook a small issue, which could have major consequences if not corrected. With over 60 locations across the nation, 4Wheel Parts own the largest chain of off-road shops in the United States. We’ve used the Raleigh, North Carolina, location many times, and enjoy working in a shop with so many genuine off-road enthusiasts.

    Coming Soon: We are just getting things started on our Adventure Grand. For our next installment, we’ll be outfitting the SUV with the protection it needs to better survive on the trail.