We're happy to say the 1999 Grand Cherokee (WJ) not only retains the excellent off road qualities that the Jeep name is synonymous for, it represents a significant improvement in virtually every area over the older Grand Cherokee (ZJ) design.

It should be said from the outset that the WJ is a completely new design, not simply a ZJ with new sheetmetal. Most of the 100 some odd carry-over parts are nuts or bolts or insignificant items like the rear view mirror. The interior and exterior have been completely redesigned, as well as the majority of the drivetrain. For us, the most interesting changes were in the drivetrain and suspension. The new body and interior designs are more a matter of taste than anything else, it's what's underneath that makes the WJ a true Jeep. What's underneath amounts to a whole lot of new parts. The engines are new or at least revised, the auto transmission is a new pseudo 5-speed design, and the transfer case is new on some models. The front four-link suspension is essentially unchanged, but the old four link rear suspension of the ZJ is gone in favor of a three-link setup. There's just not much left of the old ZJ to be found on the new Grand Cherokee.

Probably the biggest news is the discontinuation of the 5.2L and 5.9L V8s in favor of a completely new 4.7L DOHC design. While the torque and horsepower numbers of the new engine (235hp@4800rpm and 295 lb.ft.@3200rpm) are comparable to the old 5.2L, the 4.7L's strengths will show up with increased fuel efficiency and less vibration. I'll admit I wasn't too pleased to see the 5.9L retired from the Jeep line up, but rumor is there will be a larger V8 based on the 4.7L to replace the 5.9L.

The revised 4.0L (only for the WJ!) now has 5 more hp thanks to some changes in the combustion chamber, a new distributorless ignition, and new intake and exhaust designs. Not only did the changes improve efficiency and reduce emissions, but the new 4.0L is extremely quiet and smooth. The old aluminum intake was dumped in favor of steel, and the stainless steel exhaust manifold has been replaced with a two piece cast iron unit that should be much more resistant to warping or cracking than older 4.0 cast iron manifolds. These changes, along with increased material to the block, added significant weight to the engine, but dramatically reduced noise. Sitting in a brand new 4.0L powered WJ, we literally couldn't hear or feel the 4.0L running at idle, a tremendous improvement over past 4.0Ls. Sadly, the 4.0L is ready to be axed completely from the Jeep lineup in favor of a V6 similar to the new V8.

The transmission is an all new 5-speed automatic. The transmission will use one of two different second gear ratios depending on driving conditions. While in normal acceleration from a dead stop, the transmission will use a surprisingly low 3.00:1 first gear, then a 1.67:1 second gear ratio, then the typical 1:1 third. During normal cruise in third gear, smashing the gas pedal will result in a downshift to second using a 1.50:1 ratio. This transmission offers the best of both worlds for around town driving, strong acceleration from a stop using the 1.67 ratio, and high speed capability for towing a heavy load with the 1.50 ratio. For off road use, the 3.00:1 first gear ratio is a welcome change. Combined with a low range ratio of 2.72:1 and optional 3.73 axle gears, the WJ offers a low (for a stock, automatic transmission equipped vehicle) crawl ratio of 30:1. The reverse gear ratio is also 3.00:1 - now you'll be able to crawl backward as well as you can forward.

The new (optional) Quadra-Drive system with the Quadra-Trac II transfer case is where this Jeep really sets itself apart from the competition. While we're generally not big fans of OEM limited slip differentials, Jeep and Dana Corp. have developed a limited slip that works, and will continue to work for years after you've purchased the vehicle. The problem with the old Trac-Lok was premature wear of the clutches. Every time you turned a corner in a Trac-Lok equipped Jeep, you increased wear on the clutches. The new differential, referred to as Vari-Lok by Jeep and Hydra-Lok by Dana, only engages when there is a significant difference in speeds of the two tires on an axle. In other words, it works only when you need it, and the clutches wear only when you want them to wear. This is accomplished with a gerotor pump (similar to a standard engine oil pump) inside the differential. When one tire begins to slip, the pump is spun which in turn drives a piston which places pressure on the clutch plates to engage them. This same type of differential is also at work in the Quadra-Trac II transfer case, if both rear wheels begin to slip, most of the power will automatically be transferred to the front driveshaft. While our driving time with this new system has been quite limited, it appears that the Vari-Lok axles and Quadra-Trac II transfer case will be by far the most capable four wheel drive system Jeep has offered to date.

As you can probably tell, our overall impression of the new WJ is extremely positive. It's quiet, comfortable, and powerful. But the best part is that it should make any similarly priced sport ute look just plain stupid in any comparison off road. Yes, the new WJ is a true Jeep.

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Dirt Road Magazine is sponsored by Turner 4WD Parts Co.