'97-'06 Wrangler
The death of the leaf-spring Jeep suspension also meant more parts for lift kits on the new Wranglers. These kits range from 3/4-inch leveling kits to long-arm 10-inch monsters. The more height you want, the more parts you'll need. However, like the YJ, regardless of the amount of lift, we recommend a fixed-yoke kit and CV rear driveshaft (Rubicon models will only require a CV-style rear driveshaft).
Oh, sure, you can get by without one for a little while, but the vibration and steep angles can eventually damage your transfer case, rear driveshaft, or both, especially on lifts larger than 2 1/2 inches. A transfer-case drop is almost always included in a TJ lift kit and can help alleviate some vibration, but we don't see it as a long-term solution to the problem. The majority of TJ lifts include four new coils, lower control arms and sometimes upper arms, longer front and rear sway-bar links, brake-line relocators, shocks, extended bumpstops, and front and rear track-bar relocation brackets. Jeep TJs enjoy more bolt-on suspension parts than any other Jeep model, so keep in mind there are usually lots of options and upgrades when buying your lift kit. You can skip the drop pitman arm because it will cause bumpsteer unless your lift kit supplies provisions to lower the upper end of the track bar an equal amount.
With the soft-riding Jeep coil suspension, you'll need to retain both front and rear sway bars, so look for a lift kit that comes with disconnects or at least extended links for the front. The rear sway bar is light enough that it won't overly limit articulation, so rear disconnects are unnecessary. Rear shock relocators are needed to keep the shocks from being dented by the axlehousing during suspension droop. Larger lifts (4 inches and higher) can benefit greatly from new high-misalignment, adjustable track bars front and rear to locate the axles properly. Lifts larger than 4 inches will also need longer brake lines instead of the generally included relocators.
'07-and-up JK Wrangler
Partway through the production of the previous-model Wrangler, we began to see a shift in lift-kit completeness and a rise in the price of the kits for short-wheelbase Jeeps. The more extensive lift kits required fewer mandatory options. This trend seems to be sticking to the JK as well. Overall, lifts for the JK should include and will require parts that are similar to what comes with a TJ lift. Fortunately, the JK only needs 3 inches of lift to clear tires as big as 35s. Less lift means fewer corrective measures and an easier installation.
It's true the JK has fixed yokes, which in itself is an upgrade. However, the factory driveshafts are marginal for anything other than stock height, in our opinion. For any amount of lift, we'd recommend swapping out the CV-style shafts for some U-jointed driveshafts front and rear. Most lifts don't include new driveshafts, so they'll need to be sourced separately.
Lifts more than 2 inches will require new shocks and an adjustable track bar up front. Like the TJ, avoid adding a drop pitman arm unless provisions for lowering the front track bar are included as well. If the drag link is relocated, the track bar should be relocated too. Running a replacement adjustable track bar should be done without a drop pitman arm.
Some kits may come with sway-bar disconnects or have them as an option. JKs with the factory electric sway-bar disconnect don't need the potentially expensive option; you'll only need simple extensions, typically in the form of longer sway-bar links.
Longer brake lines are a good idea, or at the very, least some relocators should be included. For lifts more than 3 inches, look for frontend caster adjustment in the form of adjustable arms or cams. Your 3-plus kit should also have emergency brake cable relocators. We'd pony up for some quality shocks instead of the typically low-quality units included with some kits. Look for either a monotube or some sort of adjustable unit. It just seems like a sin to put a crappy shock on such a well-tuned suspension. The one thing that's very important with the JK is to make sure the steering wheel is dead-nuts straight. If it's not, the steering sensor for the ESP system will get angry and the system will not function properly. If your Jeep gets finicky about the lift, some scan tools can reprogram the ESP to be a little less aggressive.
'93-'04 Grand Cherokee
Chances are if you've been ogling over lift kits for your ZJ or WJ, you've found there are only a few companies producing lifts for them. The ZJs and WJs require different kits, but the concepts and designs are similar. Grand Cherokees have simple coil-spacer lifts as well as full long-arm kits available.
The '99 and '00 Grands don't have a Spicer-style U-jointed front driveshaft. These can be identified by the rubber boots at the ends of the shaft (it looks like the half-shaft from a front-wheel-drive car). Even slight amounts of lift can cause the shaft to fail. It can be upgraded with the U-joint-style driveshaft and yokes from an '01-and-later WJ. The rear driveline will benefit from the use of a fixed-yoke kit and CV driveshaft on lifts bigger than 2 inches.
All of the ZJ and WJ kits we've spotted were fairly complete. The bigger lifts should come with new lower arms all around, coils, shocks, bumpstop extensions, sway-bar links, brake-line provisions, and track-bar relocation brackets. Like the other coil-spring Jeeps, avoid a drop pitman arm unless the upper track-bar mount is lowered as well. The more complete kits include a new adjustable front track bar, which should be used regardless on lifts more than 2-3 inches.
Coil-spacer booster lifts can get you up to 2 inches higher and usually include bumpstop extensions, but not shocks.
'63-'91 FSJ
The fullsize Jeeps are very similar in componentry to the '76-'86 CJs-you're basically working with four leaf springs. FSJ lifts are almost always piecemeal and rarely come in a kit form. Always replace the U-bolts front and rear. If you have a 3/4-ton or bigger FSJ pickup, the normally recommended U-bolts are often not large enough to fit around the Dana 60 rear housing tubes, so make sure you get the correct parts. Like most of the other model Jeeps, we opt for longer stainless braided lines over brake-line relocators. A dropped pitman arm is needed for lifts more than 3 inches on FSJs, and we highly recommend replacing the factory steering stabilizer with an aftermarket unit. Even perfectly maintained FSJs have a tendency to get uncontrollable death wobble. A functioning stabilizer seems to be the only way to get it under control. Front sway-bar extensions can also be a bonus, but we've found the sway bar isn't needed for our driving habits because the lift springs are often more firm than the stock leaves.