If this chromed shock shaft looks thrashed, it's because the shock was subjected to the 2003 Baja 1000 without a shock boot. "We purposely left the boots off to see how the shocks would hold up," Kreg informed us. The deep pitting creates jagged edges, which eat shock seals with a smile. As soon as the seal goes, the oil quickly follows. No oil? That means no control. Easterners will note another concern: Pitted shock shafts are prone to rusting. Once it gets in, the rust creeps underneath the chrome, and the shaft is DOA. Fortunately, most rebuildable shocks have small parts available. If your shocks aren't made with NitroSteel shafts, consider running boots or rigging up some type of roost guard for protection
A DR exclusive is dubbed an internal limit strap. Sudden full extension is harmful to shocks and should be avoided for the best shock performance and life. DR's solution is this pair of washers included below the piston. Slightly conical, the spring steel flexes to absorb the shock's top-out force. The oil between the top-out washers further cushions the blow, making for a simple, sound innovation.
Here is the heart of the shock absorber. This assembled piston and valve-stack combo rushes up and down the shock body hundreds of thousands of times during it's life. Below the nut, holding the piston on the shock shaft, are spring-steel washers of different diameters and thick-nesses. The washers - also called a shim stack or valve stack - cover holes through which oil is forced. When enough pressure builds, one or more of the washers flex to allow oil passage. Each piston has a shim stack atop and below the piston. The top stack controls rebound; the bottom governs comression.
Here's a piston all by its lonesome. The nine holes ringing the perimeter channel oil through the piston into the compression stack. The three holes perforating the flat, inward diameter normally hide under the rebound stack.
By the time you read this, DR's new Signature-series shocks will be poised to hit the market. While it's vehicle specific shocks are test-driven and scientifically valved per the application, Signature-series shocks feature non-specific tunable settings. These shocks are nitrogen-charged and monotube, and use NitroSteel shafts. Urethane bushings line the mounting eyes for easy tuning and smooth driving in a variety of applications. The gotta-have-it billet reservoir clamps are an optional item.
Want to shave a few bucks from your suspension budget? No room for a remote reservoir? Emulsion shocks are a great option. Just like a monotube shock with a remote or piggyback reservoir, you'll find oil and nitrogen inside. The difference is that the emulsion shock does not divide the nitrogen and oil. It mingles and emulsifies inside the shock. Since nitrogen expands very little when heated, the mixture provides great performance. According to Mark Rosevear of McKenzie's Performance Products, tuning an emulsion shock isn't any different from a remote-reservoir shock. He adds that the biggest misconceptions about shocks are: 1) they will "just bolt straight up," regardless of the shock and the intended vehicle, and 2) merely buying a certain shock will make the intended vehicle ride better, without some shock tuning. "You have to spend time setting up and tuning the shocks for them to work the way they should."