One of the most important purchases any Jeep owner will make is his choice in rocker protection.
The right choice of rock slider will keep body-crushing rocks well clear of a Jeep’s costly sheet metal, while a poor choice can leave a Jeeper with thousands of dollars in body damage. Consider this JK driver, whose tube steps aren’t much different than what Smokey has worn since before I purchased her:
But, what types of rocker protection are available, and of what material are they constructed? And, which is best suited for my needs? The latter is a question I’ve pondered from the day I bought my Jeep. I’ve considered a number of options. Some were designed to take serious abuse, while others are tame in their construction.
Generally speaking, rocker protection is available in six categories (some would say five), each with its own inherent strengths and weaknesses. A few combine the features of more than one category to, hopefully, achieve a stronger product.
Skin-style rocker guards are familiar to any owner of a CJ, YJ or TJ. A simple piece of plate steel or aluminum serves to bolster the strength of the rocker panel, spreading out an impact along the length of the rocker. (Remember, aluminum saves weight, but will not provide near the strength as steel.) Most commonly in these earlier generations of Jeeps, such skins would bolt completely through the body. But, the JK’s body is formed by two (and in some places, three) layers of sheet metal with air cavities in between. As a result, JK rocker skins are held on with nutserts, small brass or steel mounts that insert into a drilled location, then crush in on themselves to provide a threaded mount for whatever bolt holds the skin in place. For JKs, these skins provide some protection, but are limited by the sheer weakness of the body to which they are mounted, to say nothing of the fact they leave the pinch seam completely exposed. And, then, there are stories across Jeep generations of the rust that can form around the holes drilled to attach rocker skins.
Body-bushing bolt mount
Rockers that attach to the two small bolts that flank the JK’s body mount get their own category here because I find their design so inherently weak as to insult any other category into which I might place them. (Worse still, a few companies have the audacity to advertise these as “frame-mounted”!) This style of slider, often offered by Chinese firms, has become popular recently due to their simple bolt-on design and enticingly low price tag. Yet, having two small bolts at each body mount as their only attachment point is asking for a breakage, either off-road or when consistently used as a step. This style of rocker guard, in my opinion, should be considered an aesthetic add-on only, and its user should not expect any true performance of it whatsoever.
In contrast to the body-bolt mount listed above, a true body-mount rock slider will afford some protection to the Jeep’s body. Body-mount sliders, such as the popular Ace Engineering rock sliders, come at a lower cost than other options and provide a simple, no-drill installation process that makes them a less intimidating purchase for new Jeepers. The drawback to a slider that utilizes these body mounts, unfortunately, is that it rests against the soft rubber body bushing. This bushing permits an enormous amount of flex between the Jeep’s body and frame. So, such sliders make a nice choice for those whose wheeling is limited to fire roads and areas free of rocks or logs that might pose an impact point. Some users choose to pair this style of rocker guard with their Jeep’s factory Rubicon rock rails in an effort to increase protection. The reality, though, is that doing so lets the new rock sliders push the Rubi rails into the body when impacted, creating the very damage the Jeeper hoped to avoid. This style of rock slider has its place, and is even something I’ve considered at times. But, ultimately, I want a slider that is prepared to protect Smokey’s body in the event a worst-case-scenario ‘oops’ is in my future.
Another economical option is a rocker rail that attaches to the Jeep’s pinch seam, that sandwiched strip of steel that sits below the rocker panel. It can be rightly said that this is the strongest part of any JK’s tub. Saying so, however, is a bit misleading, as the entire Jeep tub is constructed of steel not much thicker than an aluminum soft-drink can! Like a body-mount rocker, pinch seam designs have their place for drivers who need a suitable step and minimal protection. Any harsher use risks rolling the slider into the pinch seam, which would then bend in or out, based on the direction of the impact. The JCR Offroad Classic Rock Sliders pictured above attach to both the pinch seam and the body mount. But, given the flexible bushing previously mentioned, a dynamic off-road impact along the outermost edge would turn the tube rub guard into a lever, guaranteeing a bent pinch seam and cracked, peeling paint.
Tub-mounted boat sides
Arguably the best-looking rock sliders available, boat-side rockers like those available from Crawler Conceptz (above), Poison Spyder Customs, Nemesis Industry and a host of others have a lot to offer. These designs pair a steel or aluminum tub skin with a separate rock slider that keeps body-killing obstacles away from the Jeep’s sheet metal. Their designs also include a built-in stepping surface to make climbing in and out of a lifted Jeep that much easier. But, as the adage goes, if something seems too good to be true, it usually is. The problem with this type of rock slider is that the rocker guard is literally stronger than the body to which it is attached. As a result, one needn’t look too far to find someone whose body has been damaged or who can no longer open and close their door(s) because their boat-side rock sliders transferred the energy of an impact into their rig’s body. This is not an indictment of any of the companies producing such a design. Crawler Conceptz even went so far as to ad additional steel and bracing to the tub skin to provide a significant increase in strength. But, the problem remains that Jeep has given enthusiasts a paper-thin body that is, in my opinion, incapable of supporting sufficient protection over the long term. (Years down the road, I fully expect to see forums littered with complaints of drivers who’ve removed their sliders to see nutsert holes wallowed out by years of having 50 or more pounds of steel hanging from them.) The risk of catastrophic damage is simply too high for me to choose this style of rocker for my Jeep. It’s such a shame, as both the Crawler Conceptz Ultra Series and Nemesis Industries Billy Rockers are simply works of art!
The strongest form of Jeep JK rocker protection is a frame-mounted rock slider. Bolted or welded to the frame, this style of rock rail sacrifices an inch or two of ground clearance in order to connect these Jeep-saving devises to the strongest point of attachment on the vehicle. That said, some manufacturers will quickly point out that the JK’s frame itself is a scant tenth of an inch thick, and is itself susceptible to warping from the extreme torsion of a welded-on slider preventing the Jeep’s frame from flexing as it was designed to do. Nonetheless, hardcore Jeep JK drivers have found frame-mounted sliders to be the strongest form of protection available for current-generation Jeeps. Given the aforementioned soft-rubber body bushings, some have reported the bod itself flexing into flame-mounted sliders on hard hits or drops off rock ledges. But, there’s no insurance against life, and mounting to the frame appears to be the closest thing to an idiot-proof JK slider design.
In choosing a set of rock sliders for Smokey, I’m considering several factors:
Tub protection — Above anything else, a rock slider must protect the Jeep’s body. Otherwise, there’s no point in my spending the money on them in the first place. I may not be a hard-core wheeler, but when I screw up, I tend to do so in a big way. And, when that happens, I want to have serious protection between my Jeep and the rocks when I do.
Functional step — As a dual-purpose vehicle that has to carry my wife and two children with me, it’s imperative that whatever I choose provide an adequate stepping surface to assist us in getting up into the Jeep. While this is a minor concern now, Smokey one day will sit a few inches higher than she presently does, and I’d rather not be changing out my armor later because I didn’t think far enough ahead.
East of installation — The ideal product for me will involve little to no drilling into the body or frame. Even taking the precautions of primer and paint, anywhere I drill on my Jeep introduces a heightened possibility of rust formation compared to its factory condition. And, there’s my previously discussed feelings regarding dependency on very thin sheet metal over the long haul. So, I’ll stick to a more simplistic design, if possible.
Aesthetics – As I was recently sharing with my wife, a Jeep build is as much an artistic creation as it is a functional machine. To that end, I want something that will enhance the lines and general appearance of my Jeep. Famed architect Frank Lloyd Wright held to the axiom ‘form follows function’, and he’s absolutely right. Off-road performance must trump all other considerations. But, there’s no rule that says a Jeep has to look like something out of Mad Max going down the trail, either.
I’ve been carefully researching my options for a couple of years now, and as I near a final decision — hopefully, before Christmas — I’ve narrowed my list of choices to the following:
Poison Spyder Customs Rocker Knocker
With unassailable good looks and a long history of solid protection, I could do much worse than either the frame- or body-mounted Rocker Knocker. The body-mounted design offers a more usable stepping surface, but is slightly more likely to transfer impact forces into the body. That impact itself is less likely with the body-mounted design, though, as it sits much higher than its frame-mounted cousin. The frame-mounted version, which shares its mounts with PSC’s Ricochet Rockers, utilize two boxed triangular outriggers (three on Unlimited models) that nest alongside the Jeep’s body mounts, attaching to both the frame and the side of the body mount bracket. On my two-door, only the four bracket holes and one frame hole would require drilling, the latter being the only one I’d need to tap for threads.
VKS Fabrication’s Pre-Runner Slider
This frame-mounted design combines the beautiful plate-on-tube design of Poison Spyder’s Rocker Knocker with the bent-plate step of LoD’s Signature Series sliders. The removable rub plate protects the side of the Jeep from errant limbs or other debris and adds the unmistakable style I’ve hoped for. But, I don’t like how the VKS attachment plates will require my drilling 18 total holes in my frame, and I fear the rear attachment leg is forward enough to introduce a weakness, were the rear of the slider to take a substantial impact. I suspect that’s what’s really behind the issue discussed on one Jeep forum earlier this year.
Poison Spyder Ricochet Rocker
This is the product I’m most leaning toward at the moment. As mentioned above, the Ricochets use a very strong boxed frame mount, take advantage of three factory bolt holes to require minimal drilling and offer a generous stepping surface. And, they’re also the least expensive of my three current candidates. Really, the only thing I have against these sliders is that the totally horizontal design doesn’t offer as much body protection as the Rocker Knocker and lacks a bit in the style department. But, going this route now would also make it very easy if I ever wanted to change to the frame-mounted Rocker Knocker down the road as my children age and require less help getting in and out of the Jeep.
So, where am I off track? What factors did you consider when making a rock-slider purchase? Leave a comment below!