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James Stenabaugh photos
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
We will be testing a beautiful selection of mid-grade shocks.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
ARB Old Man Emu’s are an industry standard for shock upgrades.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
Fox 2.0 BDS are built with aluminum housings to help stand up to corrosion.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
Boss suspension units are fully adjustable and even come with female threads at both ends to fit the mount of your choice.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
Old Man Emu’s under full rebound over off-road obstacles.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
Impressive valving in the Fox dampers withheld constant punishment of full compressions and rebounds.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
Adaptable shock ends on the Boss’s allow you to invert your shocks if you so wish.
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James Stenabaugh photos
Shock and Awe - Comparing Shocks
Whatever you chose, make sure it works in conjunction with your set up.
By Pat Harrison, photos by James Stenabaugh
Comparing three different brands of shocks with our JK MetalCloak lift
They say the most important part of a vehicle is the part that connects it to the ground. Obviously, tires are rather important pieces of equipment, but what is connecting the all- important tires to the vehicle itself? If the tires spend half their time in the air, what good is one of the most expensive investments? We are here to figure that out, evaluating how a variety of shock offerings work with our new MetalCloak 89 mm (3 ½-in) Duroflex lift, and I have to admit things are going smoothly; pun intended. So let's look at the three different participants, how they vary, and how they performed in the real world.
We were trying to keep the playing field level by running products in the $140-$180 range that offered a long travel variant (255-292 mm (10-in to 11 ½-in) as dictated by our set-up) and more importantly "soft valving" for our stiff dual rate MetalCloak coils. We discovered how important it really is to pair coil rate and shock characteristic for the best results.
ARB Old Man Emu (OME): Part # 60066L front and 60067L rear
Representing the twin-tube design, this shock is a solid piece of equipment with a lot of new technology and cool features packed into it. Compared to a mono-tube design, a twin-tube shock allows for more piston travel for the same length body housing, since the bottom of the shock body is not occupied by a gas chamber. A typically higher volume of oil is allowed to transition to an outer tube where a lower pressure 50-70 psi gas chamber helps minimize cavitation and heating issues.
Instead expanding boots, OME has provided solid covers on their shocks to protect the piston shaft. Because the actual piston is housed inside the inner tube, the outer tube serves as an oil/gas chamber that can take a few knocks without affecting the shocks function. These mount body down. Like all of the mid level shock manufacturers, ARB has stepped up the design of the internals with the new Nitrocharger Sport series. Triple stage valving is the next step, and they claim performance that approaches that of remote reservoir units.
Your vehicle is suspended by the coils, which are designed to compress and then rebound back. The shock is designed to control both the compression and rebound keeping your tires firmly planted in the process. The challenge for the engineers is to offer a shock that can control these two duties almost individually. When they get it right, and you pair your aftermarket shocks properly with your vehicle, and the rate of your new taller coils, the ride quality should not be compromised. OME got it right. They offer a soft, medium and firm version of this shock so you can get it right too, no matter whose coils you are running.
FOX 2.0 PERFORMANCE SERIES: Part # 98224922-1 front, 98224959-1 rear
Both front and rears have net travel in the range of 257 mm (10 1/8-in). These FOX 2.0’s are spec'd for a JK running a lift closer to 4 ½-in according to Fox's charts. It is a gas charged monotube design that has some mind-boggling technology at work in its single piston tube. The way that various manufacturers "valve" or configure the internals in their latest products is a closely guarded proprietary subject but it is safe to say there is a lot of research and development at work here. Running a higher-pressure charge than the twin-tube design there is 180-200 psi of gas being kept separated from the oil by an internal floating piston, hence the IFP designation.
Being a relatively large body shock, the 2.0 carries more oil capacity than many monotubes and runs cooler than most due to its valving improvements and choice of materials. With these shocks intended to be mounted upright, the oversize 6061 aluminum heat dissipating body in the front may need to be spaced out a bit to avoid contact. Shock spacers and relocation brackets are available, and it's worth noting that they can really free up your choices when it comes to shock lengths and diameters, so don't get stuck thinking that the stock mount locations and orientations are your limiting factor.
BDS also subscribes to the stiff coil soft shock philosophy; therefore, MetalCloak saw fit to offer their shock in a new pairing to compliment their existing OME equipped kit. The large 16 mm (5/8-in) diameter piston shafts are hardened but exposed without boots so consider your terrain when mounting these. Now is the time to install boots if you are going to. The performance series shocks are rebuildable but you have to let the techs at Fox take care of that task.
BOSS Adjustable Hydraulic: Part # 655386 front, 595356 rear
What could be so different from the two industry standard formats found in the gas charged mono-tube and twin-tube dampers we have just discussed? "Boss" shocks fully hydraulic twin tube monsters. Unlike the technological wonders we've run so far, these massive units depend on simpler proven principals to get the job done. Being 100% oil filled with a closed cell foam insert means that these huge shocks will maintain their performance under harsh conditions. And the Aussies do like their harsh conditions don't they?
BOSS claims that their shocks will not fade under hard use, the piston and bypass tube is continually submerged in oil, keeping it cooler and displacing heat through the walls of the shock. With no gas charge putting constant pressure on the piston seals even when sitting static, this gives these units an advantage with respect to longevity. The second chamber of the twin tube design shock allows more room for oil; more oil equals better heat dispersion. Another interesting feature is that both ends of the shock have female threads allowing the customer to install any fittings to suit their application.
Then there is a curve ball thrown into the mix here that we wouldn't normally expect in this price range. Rebound damping is adjustable through a 12-position dial on the top of the tube. This allows for an impressive range of adjustment for factors such as the weight of the vehicle as well as different coil rates. On the harder settings, compression damping is also affected. If you use your Jeep to tow, or occasionally load it down with expedition gear, this adjustability might be for you.
On Road Testing:
The road course we used allowed us to literally rail the big heavy four-door Jeep JK through a series of sweeping 90-degree lefts and rights at speeds that made us thankful everything was strapped down. The stiffer coils improve road handling and they are managed so much better with quality shocks. Here all three shocks seemed to offer very similar levels of performance and ride comfort, which is not surprising considering they are all better than average products in the mid-range. No surprises to report here or standouts, just solid handling from the MetalCloak lift coils and all three sets of shocks. The valving was a good match and this was proven true by the loss of comfort in the ride when we ramped up the Boss adjustments to the higher settings just for comparison sake.
Forest Service Road (FSR) Testing:
For me this was where the tuning of these shocks really showed. Clipping through kilometres of potholes, they all soaked up the medium frequency, but more importantly, the ruts formed in the turns on these roads didn't result in unwanted drifting sessions. Keeping the tires planted and responding to steering and braking inputs isn't as easy as you think when the ground changes so damn frequently. Using three different designs, the shocks tested produce oil flow rates that have to respond quickly without allowing heat to build up, and all the decreases in performance that come with what is known as "shock fade".
We got to see firsthand how the multistage valving on the Fox and OMEs were responding to the variety of impacts that our FSR driving produced. I thought the Fox 2.0’s were going to be a little stiffer than they were, given the amount of effort required to compress them during the install. But they were very plush in all stages of testing and stayed that way, providing predictable handling characteristics that boost the bravado quotient.
The OME Nitrochargers were in the middle of the pack for perceived stiffness but performed solidly on large and small hits. Easy to see why MetalCloak paired up with them in the first place. The big Boss units took a while to dial in what we figured to be the best setting and stayed the coolest, however they felt the least responsive at higher speeds. We covered extended stretches of FSR and stopped to check each set of shocks for heat build up and encountered nothing but ‘warm-to-the-touch' in each case.
Off Road Testing:
Finally, we head off the beaten track where the terrain will have the pistons and shafts travelling through their full range of compressions and extensions. Here the improvements in seals, oil flow rates, internal bumpers and each shocks ability to stay cool are really put to the test. If you've done your parts selection properly, you should be able to realize as much tire and suspension droop as possible without maxing out the shocks travel at either end.
Once again, each set of shocks stayed cool and provided better levels of damping than our previous generic set up ever did. It's like you suddenly got better at off-roading. The high-zoot valving in the OMEs and the Fox shocks was evident as we took big hits slowly and dropped off the odd ledge that had them going from fully extended to bouncing off the bump stops in an instant. The monstrous Boss units kept up well here and their shear size gave you confidence to go a little harder. We experienced no fade and noticed no loss in performance even though we were literally bouncing around like pinballs in an arcade game.
CONCLUSIONS:
ARB Old Man Emu Twin-Tubes.
The old saying that you get what you pay for holds true here in the shock world. There really isn't much in the way of cons with these Australian offerings and a lot of pros. Solid covers for the piston rods, plush performance thanks to the technology packed inside available in soft, medium and firm valving depending on your coil selection. These new Nitrochargers are quite an improvement over their predecessors. The minor cons I came up with are that they are not rebuildable, mount in only one configuration and come in a yellow finish that was already showing signs of wear when they arrived. If you share the sentiments of our brother from down under, and place more emphasis on performance than aesthetics, you likely won’t care.
Fox 2.0 BDS Monotubes
Fox has been around for quite awhile and they know how to make a monotube work like it should. Throw in the fact that this mid-range offering is rebuildable, and you are looking at a potential long-term relationship. Sexy looks and heat dissipating aluminum make them a popular choice. Solid performance and a great feel make them a smart one too. If you are hard on your equipment and understand there is a price to be paid for way you play, then these will probably keep up. Things to keep in mind are that the monotube body won’t take any hits, the shocks don't come with boots to protect those shafts, and that sexy finish seems to get old quickly. Still a solid value for the long travel monotube.
BOSS Hydraulic:
Some people will tell you there is no way a fully hydraulic shock using an expanding foam cell to control cavitation, can possibly compete with the modern engineering of the wonder units of today. I can only tell you that these monstrous twin-tubes performed almost as well as the other participants here, and did so while providing a couple of features not normally found at this price point. There is a lot to be said about adjustability. Seems you can now match the shock to your coil, your weight, and your personal preference, all in one standardized design available in plenty of lengths. Mount it any way you want. The Boss units are not as plush as their counterparts, nor as sexy, but this is a contender nonetheless. You can't rebuild them but they will take a beating long after others require attention. If you tow, overland or weigh your off-road rig down with gear then you'll want to consider these adjustable work horses.
No matter what lift kit you run or what level of use you plan to subject your off-road capable vehicle to, take the time to pair up the proper shocks for the task. Valving, travel length and cost are all important factors to consider during the process. Give your ride a fighting chance by stepping it up a level to any one of these quality units and you will be glad you did. Who knew it would turn out to be one of the best improvements we've done on our rig to date?
Click here to watch the video "Testing Old Man Emu Shocks".