Jeep Grand Cherokee and Commander

The new-generation Jeep Grand Cherokee (WK) and '06 XK Commander have been panned by hardcore off-roaders as being too pavement-oriented because of their unibody construction and independent front suspensions. This vocal-minority grumbling didn't discourage Superlift from engineering lift systems for both 4WD and 2WD versions of these new Jeeps, because Superlift strives to have the widest range of lift systems and accessories in the off-roading industry.

Designed in cooperation with American Expedition Vehicles (see sidebar), the new Superlift 4-inch systems maintain these Jeep SUVs' tame on-road ride while improving their off-road potential. Ground clearance improves through creating space for up to 33x12.50 tires on 8.5-inch wheels with a maximum 5.75-inch backspacing (to retain the factory wheels, minimum 3/4-inch-thick spacers are required for knuckle clearance).

PartsSuperlift applies its Frame Integrated Technology (F.I.T.) IFS approach to the WK/XK kit. Key components are replacement ductile-iron steering knuckles with a stout bellypan/crossmember assembly. These knuckles and the high-clearance crossmember help relocate the differential (4x4 application only) and lower control arms to maintain factory geometry: CV axles, steering linkage, and wheel alignment stay within spec. The 4x4 version of the kit also addresses front driveline angles so that the factory driveshaft can be retained. Underneath, Superlift contours the kit's interlocking crossmember and full-width bellypan for maximum ground clearance, using countersunk fasteners. This subframe structure relocates the lower control arms and improves the WK/XK's overall stability.

Superlift enhances ride quality in the front by adding preload spacers and tower blocks to the stock coilover strut assemblies. The preload plates increase the spring rate slightly to minimize mushiness and compensate for the increased weight and offset created by larger tires and wheels. Extended factory-style front and rear antisway-bar links ensure proper bar preload to further tune the road ride.

In the rear, Superlift eliminates the inherent sponginess by using longer coils that have a slightly heavier rate than stock. The kit's relocation brackets maintain correct four-link geometry.

Customers can choose between two grades of rear shocks, both of which are valved specifically for the XK/WK: standard Superlift Superide hydraulics or premium Superide SSR remote-reservoir shocks, which are trick-looking, high-pressure monotube units.

In addition to shock choice, customers can also add optional eXtreme Ring differential cover protectors. These and all other Superlift components are covered by a limited lifetime warranty.

Note that if the Jeep is equipped with Electronic Stability Program (ESP), premature system engagement may occur after installing any lift system: ESP function is impacted by tire size, wheel offset, and other factors. If ESP routinely activates, the driver can disable the system by pushing the "off" button located in the center stack of the dash. ESP is also affected by steering-wheel position, and the system must be disabled with each key cycle if the steering wheel isn't centered. Superlift and AEV are working on an ESP recalibration system; check their websites for the latest information.

InstallationSpecialized tools and fabrication skills (4x4 system only) are required. Because of this, Superlift recommends that the job be performed by a qualified professional. The photos and captions here provide an overview of the process as performed on a 4x4 Grand Cherokee; the 4x2 kit deletes the front differential relocation parts and doesn't require the frame welding and exhaust clearancing.

Preparation involves applying pieces of tape to the steering wheel and column to mark their alignment. The steering wheel is recentered following the lift. It is also necessary to unbolt the rear track bar at the axle and disconnect the battery's negative cable before raising and securing the Jeep. Referring to a service manual while removing the OE skidplate, sway bars, brakes, knuckles, front axleshafts, struts, and other factory suspension components is a good idea. Superlift's comprehensive and well-illustrated instructions detail each step.

The end results: an even grander Grand and a Commander that might actually command some respect from crusty old off-roaders.

The Superlift 4-inch WK/XK system features replacement ductile-iron steering knuckles, front coilover preload spacers and towers, extended sway-bar links, a front crossmember and bellypan, differential and front driveshaft relocation/clearance pieces (4WD kit only; shown), longer rear coils, link arm and track bar relocation brackets, and all other necessary hardware.
The Superlift 4-inch WK/XK system features replacement ductile-iron steering knuckles, fro
In the front, one of the final disassembly steps is to remove the diff. A trans jack helps immensely.
In the front, one of the final disassembly steps is to remove the diff. A trans jack help
Here's the gutted front end awaiting the Superlift components.

The rear front-suspension crossmember must be notched for front driveshaft clearance. The instruction sheet includes a template, which is located over a factory skidplate mounting hole.
The rear front-suspension crossmember must be notched for front driveshaft clearance. The
After the template is outlined, a plasma cutter or torch is used to remove the area inside the line.
After the template is outlined, a plasma cutter or torch is used to remove the area inside
Here's the cut-out section.

We testfit the kit's reinforcement plate in the newly created notch then trimmed the crossmember to fine-tune the fit. We then snaked the crossmember with a magnet to remove any slag or shavings.
We testfit the kit's reinforcement plate in the newly created notch then trimmed the cross
After verifying that the patch plate fit properly, it was welded into place.
The additional clearance is necessary because the front diff will be remounted a couple inches lower than stock. To inhibit rust, the bare metal should be painted after it cools.
The additional clearance is necessary because the front diff will be remounted a couple in

The diff's lower mount was removed. It will be repositioned on a Superlift bracket.
We used the kit's diff bracket as a template for marking the lower mounting area.
Then we removed the Superlift bracket and cut off the diff's mounting ear (using a torch or plasma cutter will warp and irreparably damage the diff's housing).
Then we removed the Superlift bracket and cut off the diff's mounting ear (using a torch o

We reinstalled the Superlift diff bracket and then attached the factory mount to it.
On the driver-side framerail, the kit's diff spacers installed on the factory mounts.
Similarly, we installed the kit's passenger-side diff drop brackets to the factory location.
Similarly, we installed the kit's passenger-side diff drop brackets to the factory locatio

We then used an able-bodied assistant (a trans jack also works) to install the diff in its new mounting locations. Like many of the fasteners, hardware for this step is snugged but not final-torqued until later.
We then used an able-bodied assistant (a trans jack also works) to install the diff in its
The diff housing's protrusion just below its cover also needed to be trimmed (fluid loss was minimized by waiting to trim until the diff was remounted on the vehicle).
The diff housing's protrusion just below its cover also needed to be trimmed (fluid loss w
Even though the differential is attached to the frame, it moves a little under load, causing the driveshaft to rub on the exhaust crossover pipe. Therefore, the pipe must be dimpled. We test-fit the driveshaft to determine the potential contact area and then removed the driveshaft, heated the exhaust tube in the appropriate spot, and dimpled the tubing with a ball-peen hammer. Once the pipe has cooled, the driveshaft can be reinstalled.
Even though the differential is attached to the frame, it moves a little under load, causi

The lower control-arm mounts' lower lips must be trimmed.
The full-width Superlift front crossmember mounts to the stock lower-control arm holes and doubles as a sturdy subframe.
The full-width Superlift front crossmember mounts to the stock lower-control arm holes and
A short preload spacer must be installed, which requires disassembling the strut with a special compressor tool. Once accomplished, we bolted the shock towers on top of the coilover assemblies.
A short preload spacer must be installed, which requires disassembling the strut with a sp

The properly oriented struts were installed to upper mounts. Underhood components, such as the coolant reservoir, that were moved to access the upper strut hardware were then remounted in their factory locations.
The properly oriented struts were installed to upper mounts. Underhood components, such a
The factory lower control-arm mounts were rotated 180 degrees, and the arms were then mounted to the bottom of the rear crossmember and to the Superlift front crossmember. Then, the axleshafts and struts' clevis ends were installed.
The factory lower control-arm mounts were rotated 180 degrees, and the arms were then moun
We made sure to note the orientation of the dustshields and ABS sensors before transplanting the hub/rotor assemblies to the Superlift knuckles.
We made sure to note the orientation of the dustshields and ABS sensors before transplanti

Comparison of the stock knuckle (left) to the Superlift unit following the component swap illustrates how lift is achieved through wider spacing of the control arms.
Comparison of the stock knuckle (left) to the Superlift unit following the component swap
We installed the new knuckles by lining up the axleshaft splines and ball joints. The calipers went on next. Superlift includes brakeline extension brackets, and the instructions illustrate brake hose and ABS wire routing.
We installed the new knuckles by lining up the axleshaft splines and ball joints. The cal
Next on were the kit's factory-style extended sway-bar links.

Front-end assembly was completed by installing the bellypan. It and the Superlift crossmember are contoured for maximum ground clearance and are secured using countersunk fasteners.
Front-end assembly was completed by installing the bellypan. It and the Superlift crossme
The rear lift began by removing the shocks, sway-bar links, and coil springs.
We removed the lower links at the frame, cutting the factory bolt that wouldn't clear the gas tank. We installed the Superlift drop brackets using the factory holes and reconnected the lower links with a combination of existing and supplied hardware.
We removed the lower links at the frame, cutting the factory bolt that wouldn't clear the

Then, we removed the upper links. We used a Superlift upper link-arm bracket as a template on each side to drill three additional holes in each factory mount.
Then, we removed the upper links. We used a Superlift upper link-arm bracket as a templat
Next, we installed the brackets with the supplied hardware.
The Superlift reinforcement plate was installed, and the track bar extension bracket was positioned on the factory mount.
The Superlift reinforcement plate was installed, and the track bar extension bracket was p

After verifying that the bracket's track bar hole was plumb with the factory one, the additional mounting hole was drilled.
After verifying that the bracket's track bar hole was plumb with the factory one, the addi
The kit's compression stop extensions installed on the coil towers and reused the factory snubbers. Then, the Superlift extended factory-style sway-bar links were installed after their bushings and sleeves were inserted.
The kit's compression stop extensions installed on the coil towers and reused the factory
The axle was lowered until the Superlift springs seated properly in the factory locations.

Rear button-up details included installing new shocks (optional Superlift SS monotubes by Bilstein shown here) and adding the kit's brake-line extension brackets (visible behind the sway-bar link).
Rear button-up details included installing new shocks (optional Superlift SS monotubes by
The shocks' remote reservoirs mount out of harm's way on the frame near the spare tire.
Kit options include eXtreme Rings diff-cover protectors and SSR (monotube remote-reservoir) shocks, which are valved specifically for the application.
Kit options include eXtreme Rings diff-cover protectors and SSR (monotube remote-reservoir

AEV Takes Jeeps to a Higher Level

American Expedition Vehicles (AEV) grabbed the Jeep world by the throat in the late '90s with its stretched-wheelbase Wrangler 112 concept vehicle. DaimlerChrysler took note of this and other AEV innovations such as integrated rocker-panel protection, subsequently making these features available off the assembly line. AEV has also won three DaimlerChrysler Design Excellence Awards for its custom Jeep vehicles.

In late 2004, AEV contacted Superlift for design assistance with its Mojave Grand Cherokee project. "We originally approached Superlift for a few reasons," says AEV founder Dave Harriton. "We knew the WK/XK platform would be a great seller if it were done right, so it made sense to invest in a high-quality suspension. Superlift was chosen because [they are] one of the few suspension companies to have all [their] own manufacturing in house. That makes prototype and development much easier and less expensive. Also, I had previously worked with Superlift's head engineer, Kevin Dill (who was responsible for the Atlas transfer case). Kevin really did a great job with the suspension, and we tested and tweaked it for over a year. Customers who purchase this lift are not going to tolerate poor handling, poor driveabilty, or any of the other typical shortcomings that most suspension companies can get away with on vehicles like Wranglers and pickups."

The Electronic Stability Program presented the biggest engineering challenge. "It really is an incredible system in terms of safety, but when you modify a vehicle with a lift kit, the ESP tends to go nuts," Dave Harriton says. "So the primary delay in getting the kit to market has been developing the necessary hardware and software to compensate for the lift."

AEV offers the lift installed on its new "trail-ready" Grand Cherokee and Commander conversions.