A Glimpse Inside Bilstein Off-Road Shock Absorbers

When the going gets tough, the tough upgrade to Bilstein shock absorbers. It is that or they say screw it and go full Unimog.

However, not all of us petrol-powered peasants have the financial capital to splurge $200,000-plus on a twin-turbo V8 slab of over-engineered German sledgehammer ingenuity. And thus, we mod what we’ve got and turn toward the best in the biz. This is precisely why we geeked out when we caught up with the Bilstein team at Easter Jeep Safari 2022 a few months back.

While searching out new content, the brand’s display rack topic came into question. This is when Bilstein’s Technical Service and Off-Road Advisor, Junior Africa, gave us the run-down on some nifty notes regarding their product lineup.

One of the more intriguing offerings was the Bilstein’s B8 ZoneControl 8112 Shock Absorbers. This product caught our eye a couple of years back when we first witnessed Bilstein’s behind-the-scenes B8 build video. So to keep things tidy, take a look at the video. The following notes pertain to each product on display and don’t forget to drop any questions you might have in the comments section below.

Bilstein B6 4600

Intended to be a direct bolt-in upgrade for daily drivers and mild weekend-warriors, the B6 4600 is a monotube design engineered with the budget-minded truck, SUV, and 4×4 driver in mind.

Like much of Bilstein’s portfolio, the B6 4600 comes packed with a nitrogen-pressurized 46mm tube. Inside, a floating dividing piston keeps the gas and oil separated and maintains a tolerable ride. This helps bolste “fade-free performance.” Bilstein attributes this in large part to the brand’s patented adaptive digressive valving.

B8 5100

B8 5100 shocks are a ride-height, preload adjustable setup and come tuned around specific vehicle applications. As with the B6 4600, the B8 line utilizes Bilstein’s digressive valving to react to changing surface conditions. The result is a more predictable and comfortable ride over stock-shocks. The B8 5100 products can handle the additional load capacity of even the heftiest collage of camping and overlanding gear.


B8 5160

From there, we move on to the B8 5160 remote-reservoir setups. These units come zinc plated for added durability and they look great too. The featured benefit of a reservoir is the increased bump in oil capacity which will maintain extended performance.

The addition of the B8 5160’s reservoir mounts grant the driver an increased feel for ground control. It also helps disperse the heat-soak that inevitably comes from prolonged abuse in off-road scenarios. These kits even come with an optional billet-aluminum reservoir clamp for those in search of a flush look.

B8 6112

Upgrading to Bilstein’s B8 6112 units grant you access to a larger 60mm digressive piston, and an integrated adjustable coilover spring. This setup offers improved damping control and is intended to be mounted at a vehicle’s factory mounting points. Each kit comes equipped with an adjustable spring seat. The B8 6112 is ideal for leveling, lifting, and affixing dedicated off-road tires on all four corners.

Multi-tiered snap-ring grooves integrated into the body of the shock give spring seating positions ranging from 0 to 2.75 inches. Furthermore, all B8 6112 shocks are produced with direct-fit installation in mind, making them a breeze to install and adjust.


B8 8112 ZoneControl CR

Bilstein’s B8 8112 ZoneControl CR is the sort of high-performance shock that serious off-road enthusiasts geek out over.

The internal design incorporates position-sensitive damping in both compression and rebound. ZoneControl CR setups are about as good as it gets when the asphalt exits stage left. That’s not to say that daily driving comfort is not a key focus, hence the infinite adjustability range. Bilstein fully understands that on-road driving characteristics are just as important.

Highly capable, thanks in part to its position-sensitive damping. Each ZoneControl CR unit comes with three compression zones and two rebound zones, each controlled by three independent pistons.

Breaking it down into specific features and benefits looks like this:

  • Bottoming out is no longer a concern thanks to the internally mounted telescoping compression stop. The need for an external hydraulic bump stop is also eliminated.
  • The design’s secondary rebound stop absorbs spring energy, a huge perk for when retaining control, post impact. This also reduces the effects of top-out and eliminates external limit straps from the equation entirely.
  • A “Jounce Cut Off” (JCO) system provides a backup compression valve piston kicking in. The aforementioned two-stage telescoping internal compression stop also negates an external hydraulic bump stop.
  • A Rebound Cut Off (RCO) consists of a dual component structure. Both a secondary rebound valve piston and an internal rebound stop allow the RCO to “decelerate” the spring. A safety net of sorts, that is only activated when the RCO’s secondary piston triggers the rebound stop.

B8 8100 (Bypass)

Bilstein’s B8 8100 bypass shocks are fully tunable; rear shocks are a direct fit and offer position-sensitive damping. An ideal solution for light trucks and SUVs that see heavy off-road abuse. These offer comfortable ride quality, impressive bottom-out ratings, and dual-tube external bypasses with independent damping adjustability for both rebound and compression.

The 8100s can be tuned around particular applications with a bevy of damping adjustments. An “incremental flow adjuster” setting allows you to tweak things to the extreme. Supported by a 60mm anodized aluminum piston that’s been loaded with an 18mm piston rod for greater damping control, these bypass shock absorbers are equal parts smooth operator and beast mode. Billet rod ends and vulcanized mounts allow OE fitment without any fuss.

There’s also a “Bump Zone” right above the compression bypass tube for even more compression control. Again, no need for a hydraulic bump stop. These B8 8100 Bypass shocks are usually accompanied by the 8125 coilovers.

M 9200

Finally, there’s the M 9200 universal off-road line from Bilstein, which is designed for race applications. These thoroughbreds can be paired with the M 9200 Coilovers.

In bypass form, these shock absorbers are equally position-sensitive and adjustable, opening you up to a world of damping tunability. Rocking a thick 70mm circumference, 9200a are available in both four-tube and three-tube structures. Externally adjustable bypass shocks are a brilliant universal tuning solution for hardcore crawlers, go-fast desert racers, and dune jumpers alike.

Sold by size and performance thresholds, these are the types of shocks that you build an entire fenderwell around, fabricated chassis components, and one-off builds.

The Bilstein booth at Easter Jeep Safari 2022 did not disappoint!

Parting Departure Angles

Every offering from Bilstein offers its own perks and appeal for various off-road applications. The cutaway of those ZoneControl CR multi-stage shock absorbers was hands down the coolest highlight. It is neat to know the established old guard of Bilstein has the technical capacity for continued innovation. Seeing Junior present the cutaway suspension components, we can ponder about what other great off-road engineerings are around the corner.



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Micah Wright

Raised on LEGOs by grandfathers who insisted on fixing everything themselves, Micah has been a petrolhead in training since age four. His favorite past times include craft beer, strong cigars, fast cars, and culinary creativity in all of its forms.
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