Trail Upgrades Jeep and Ram Chassis

Words: Larry Shepard

The basic Jeep® has been around since the early 1940s and there have been many variations over these last 60-plus years. I’ll try to limit this discussion to the newer models due to space limitations for this column. I originally wanted to use “off-road” in the title but during the 1970s and 1980s, the term off-road was used for racing parts that were not used on-road. Off-road Jeep vehicles travel both off-road and on-road, so that can be confusing. These off-road parts and kits are for off-road through the woods and over rocks and across streams. Our first major Jeep kit was the 1981–1990 4.2L in-line six multi-point fuel injection kit (P5249686AE, automatic), which is still very popular. Then we did cold-air systems such as the 1991–2001 4.0L Cherokee (P5007830, oiled) and Cat-Back™ Exhaust Systems, an example of which is the 2007–2009 3.8L V-6 Wrangler (P5153858). These parts all relate to the engine and I will limit this article to chassis items, centering on lift kits.

You might think that a lift kit is merely a spring-and-shock deal, but it is much more complicated than that. There are many models to consider, for instance the “JK” or 2007–2010 Wrangler and then 2WD or 4WD and two or four-door aspects, along with items like tire size. With all this to figure out, you might ask the question—why install a lift kit? There are many reasons, but vehicle appearance and vehicle attitude seem popular. If the vehicle goes in the woods and over rocks, then ground clearance is important and lift kits increase ground clearance. Lift kits also increase tire clearance and larger tires are desired for many reasons. Increasing the vehicle’s wheel travel is also desired for trails, rocks and streams.

A lift kit raises the vehicle using springs, but springs can also be used to change the vehicle height in the negative direction. These are called lowering kits. There is a four spring lowering kit for the 2006–2008 Jeep Commander, 5.7L V-8 (P5153728), which drops the front three-quarters of an inch and the rear one-and-a-half inches. There is also a lowering kit for the 2006–2008 Ram (P5155066). Obviously, a lowering kit would be an on-road appearance item and not an off-road package.

Another new package related to vehicle height is the leveling kit(s), and several are offered for various Ram truck models, like the 2.0" lift, leveling kit (P5155394) for the 2003–2004 Ram 2500 (DR) and the 2005–2009 Ram 2500 & 3500 (DR/DH). The term leveling comes into play to allow the customer to compensate for big, heavy bumpers/hitches (snowplow) that may have been added to the front, and/or giant tool boxes and such that may have been added to the rear. The extra weight causes the vehicle heights to change, so the leveling kit allows you to get the vehicle back level with all the added hardware.

A lift kit is a very general term. The key feature or technical yardstick for lift kits is height—how high does it lift the vehicle over the stock or production height. Sounds simple but you must be very cautious! The first step in lift kits fits in the 1.5" to 2" lift range and they tend to be coil spacer kits. The key word is spacer because the provided spacer fits between the coil spring and the spring seat and raises the vehicle using the stock coil springs. The 1.75" lift kit for the 1993–1998 Grand Cherokee (P5155382) and the 1.75" kit for the 1997–2006 Wrangler (TJ) are examples of coil spacer kits. These kits tend to be the least expensive and easiest to install, and are designed mainly for the customer who wants to use bigger tires. They are not generally recommended for difficult trail use.

The 2" coil spring lift kits are much more complicated than the spacer-style kits, which means there are a lot more parts in the box. The four coil springs and four shocks are just the beginning. The 2007–2010 Wrangler (JK) kit (P5155207) is a good example. The longer coil springs have an increased rate that is matched to the premium shock absorbers to provide unmatched ride quality and handling, both on-road and on the trails. There are new adjustable alignment cams that allow you to correct the caster angle caused by the increased vehicle height. There are also longer sway bar links with greasable, factory type ends. And there’s a lot more in the kit, from hardware to brackets to bolts, which will make your job easier. There are two similar 3" lift kits for the 1997–2002 Wrangler (TJ) (P5155373) and the 2003–2006 Wrangler (TJ) (P5155374). The 2" lift is ideal for 33" to 35" diameter tires. Note: On 2WD Jeep vehicles, the amount of lift is closer to 3", because these 2WD vehicles weigh less than the 4WD versions. The ultimate off-road package is the 4.5" lift kit (P5155075) for the 2007–2009 Wrangler (JK). The key to this package is the longer, high-articulation axle-to-frame link arms. By raising the vehicle 4.5", you also receive longer brake hoses and parking brake relocation brackets. Everything is designed to work together. This package is best suited to 37" diameter tires. The 4.5" lift kit also requires special service parts (stock hardware won’t get the job done) mainly because they are the most common parts to be broken or damaged in the off-road/trails environment: front driveshaft (P5155119), rear driveshaft (P5155120), front shock (P5155116) and rear shock (P5155117), all for the for 2007–2009 Jeep Wrangler. Note: The driveshaft assembly has U-joints on each end and the U-joints tend to be the weak links in off-road usage, so it is helpful for the customer to have service units that come as an assembly with U-joints.

There are also 3" lift kits for the 1976–1981 Wrangler (CJ) (P5155368) and 1981–1986 CJ (P5155369), a 1.5" lift kit for the 1987–1995 YJ (P5155370), a 3.5" lift kit for the 1987–1995 YJ (P5155371), and a 4" lift kit for the 2009 Ram 1500 (P5155393).

If you plan on using your vehicle as the ultimate off-road performer, which is related to the 4.5" lift kit and the big, 37" tires discussed above, the next upgrade is the front and rear axles. The basis for these upgrade units is the 2007 Jeep Wrangler Rubicon model. These HD units are considered Dana 44 designs, although they are upgraded from the basic 44 unit. Many Jeep vehicles used a smaller Dana 35 or similar unit in stock configuration, but there was high demand to use the 44; the introduction of the Rubicon option did just that. These Rubicon-based units are available for upgrade use without having to find an older Rubicon model. The 2007–2009 Wrangler Dana 44 front axle is P5155252 (no brakes). There is also a JK Dana 44 front assembly modified for use in TJ models (P5155256). One of the somewhat unknown secrets of the Wrangler is the Egyptian military Jeep, called the J8, which uses a special leaf-spring style rear suspension and the Dana 60 rear axle. These vehicles are hard to find. The J8 leaf-spring style Dana 60 axle (P5155083) comes with a 5 on 5.5 hub. The J8 Dana 60 axle, modified for the JK Wranglers (P5155260) comes with a 5 x 5.5 and 5 x 5.0 bolt pattern (4.10 ratio with limited slip). Note: Regarding applications not listed, we recommend taking the vehicle to a professional off-road shop for these modifications.

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Jeep and Ram Chassis Upgrades - PDF