Six Shooter Driveshaft Couplers - Coupler Therapy

Torque is a stone-cold killer. While its more flamboyant partner, Horsepower, rakes in the magazine headlines and dyno-chart hosannas, Torque wages a quiet but unceasing campaign of mechanical mayhem against your Corvette's drivetrain, methodically seeking out the most vulnerable parts in the hardware chain and reducing them to smoldering handfuls of metallic granola.

Maybe you've been lucky, and your dealings with Torque have thus far been limited to the occasional lurid burnout or spine-straightening blast of straight-line acceleration. But if you ever plan to push your car to its limits on a racetrack, or enhance the output of its engine with aftermarket parts, chances are that your relationship with this twisted dynamo will eventually take a darker turn.

Fortunately, the current and previous Corvette generations are by now something of a known commodity, their chief structural weaknesses having long since been exposed on dragstrips and road courses around the world. Such experiences have prompted the development of a variety of heavy-duty replacement parts intended to better withstand Torque's destructive influence, and knowing which of these parts to deploy throughout your C5/C6's driveline can help ensure that everything stays together as you turn up the wick.

Two of the more failure-prone bits in the factory setup are the stock driveshaft couplers, which serve the dual purposes of attaching the shaft at either end while minimizing the transmission of noise and vibration into the body and passenger compartment. While the couplers work well in normal and light performance driving, their rubber construction makes them ill suited for use in high-output, high-rpm applications.

Early aftermarket replacement couplers were made of solid aluminum, which solved the frangibility problem at the expense of greatly increased NVH levels. The solution, developed by Prothane, came in the form of an aluminum coupler equipped with heavy-duty polyurethane bushings. Dubbed the Six Shooter for its resemblance to the cylinder of a revolver-type firearm, this unit is claimed to combine the durability of a solid-metal piece with the vibration-quelling properties of the factory rubber coupler.

When an acquaintance's '01 C5 went into the shop recently for a clutch replacement, we capitalized on the opportunity to obtain a pair of Six Shooters from Vette-parts mega-retailer Zip Corvette and bolt them up in place of the stockers. Zip VP Justin Abbott has installed the Six Shooters on numerous C5s and C6s in the recent past, so he has considerable insight regarding the need for this upgrade.

"Any [car] that is getting sticky tires, for either drag racing or road racing, or power adders such as a supercharger, turbo, nitrous--even a head-and-cam package" is a good candidate for the Six Shooters, Abbott told us. He added that manual-trans cars have a higher risk of coupler failure than do automatic ones, due to the higher shock placed on the driveline by the more-direct flywheel/clutch interface.

With our Six Shooters in hand, we moseyed over to Seffner, Florida--based performance tuner AntiVenom to document the R&R. Follow along as we take a closer look at the process, and get some inside information on a few of your Corvette's less-commonly discussed drivetrain components.