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WRX Rear Shifter Bushing Install

Low-scale, easy mods are rewarding

Right now we're working on the theory that you can spend a few bucks on a small performance modification and it'll still be worthwhile. Think of it this way: Simple to install; low-stress components; easily appreciated functional improvement. Certainly, fun is relative. A $2,000 turbocharger and the supporting cast of fuel and spark will probably light your pants on fire, but that's an expensive, involved mod. We spent a few dollars on a bushing, installed it in an hour (taking our time) and can feel the improvement as clear as day.

Be Direct

Kartboy's rear shifter bushing is a $35 piece, and it's universal to most all-wheel drive Subies with the manual. It mounts within the drivetrain tunnel, at the rear of the gearbox cavity. Two bolts. Manufactured with a stiff polyurethane, this bushing receives the butt of the gearshift-actuator rod. It's far firmer than the mushy factory unit it replaces, which has about as much structure as a hippie commune. Kartboy also manufactures bushings for the front-end of the actuator rod (among other performance hardware—visit kartboy.com), so coupled with the rear bushing you're essentially locating the actuator rod between two masses of stout poly. Together they increase the directness of shifter movement twofold.

The Subaru Impreza's shift mechanism, WRX included, is pretty soft as shifters go. Not General Motors soft, but far less satisfying than an Integra shifter, and not even in the same league as the Miata's near-Nirvana OEM short-throw. With a few parts (Kartboy's bushings, acted on by a short-throw shifter) the gear selection experience for all WRXs is heightened dramatically. Still no Miata, but few factory shifters will ever compare to that. The WRX short-throw is an awfully nice upgrade, though, and this neat little rear-actuator bushing is the final touch.

The Basics

Basic wrenching stuff: Use jackstands, please. A jack alone isn't safe, and ramps won't raise the car far enough unless you're really skinny. While you're under there, it's a great time to change the gear-lube. Lots of all-wheel-drive types have experimented with different lubricants for the WRX manual-trans. It's an old gearbox design, and not very tolerant. Subaru went cheap when they spec'd this five-speed for the WRX. The STi's six-speed was already available in Japan, but they cut costs and corners with a weak five-speed that had already paid for its tooling. Anyway.

Located above the front driveshaft about parallel with the middle of the WRX's front door, the small original-equipment rear shift-actuator bushing is secured with two bolts that attach to the floor pan. These will not be reused, as the Kartboy bushing is deeper than the OEM unit, and comes with its own bolts. They won't be too tight, as this is a low-impact part. Once the original bolts are out, you'll need to remove the through-bolt holding the front end of the actuator in place around the forward shift-actuator bushing. This will free the actuator rod enough to slide it forward, and pop it out of the rear OEM bushing. Working with the actuator linkage and bushings is eased by unplugging the O-2 sensor so the O-2 cable won't be underfoot (be gentle, they're pricey).

Easy Install

The bolts attaching the rear shifter bushing are reached more easily with lots of extensions. Almost everything here is a 12mm, so it's not a bad idea to keep two sockets and a 12mm combination wrench under the car with you. Before you install the rear shifter bushing, lubricate the interference surface (where the actuator goes) with something heavy and slimy. Bearing grease would work, but we had some leftover bushing grease from our Hotchkis anti-roll bars and used that. It's nasty stuff but it sticks around. Be sure to install the new bushing facing the right direction. You could easily flip the thing upside down without noticing, and give yourself a headache making the bolts line up with the threads. The shift-actuator receiver should be pointing slightly upward, essentially towards the grille of the car.

Kartboy's rear shifter bushing is an easy install. You can perform all the details necessary in less than an hour, and the improvement, though minor, is noticeable. Shift-throw accuracy improves, and gears pop into place with a tad more authority. Every little bit helps, right. The satisfaction of completing the work without the extended cussing and drawn-out thought processes of involved installs can't be overlooked, either. We were able to tie up some vagrant shifter movement, and while under the car we drained some uncooperative synthetic gear. Less stress and multiple layers of improvement netted by just one upgrade.