The factory shifter in the 2015-2021 Subaru WRX has more side-to-side room around first and second gear than it needs. The PERRIN shift stop closes that extra space at the shifter assembly. The PERRIN brass bushing tackles a different source of softness by replacing the rubber bushing at the transmission end of the shift cable.
Quick answer: the shift stop made the bigger immediate difference on our 2017 WRX. Side-to-side play dropped dramatically, especially around first and second. The brass bushing made the shifter feel more solid through the rest of the shift. We installed them at different times, so the effects were easy to separate.
On our WRX: The shift stop was cheap, easy to install, and made a huge improvement in the side-to-side play. Setting the gap took a little adjustment, but it was not a difficult install. Once tightened, it stayed put and has never needed retightening. We added the brass bushing later. The stock shifter did not feel unusually rubbery beforehand, but the more solid feel was obvious once the brass bushing was installed. It did not add any vibration.
The shift stop is an easy mod to recommend because it is inexpensive, simple to install, and makes an immediately noticeable difference. The bushing is a smaller refinement: you may not think the factory piece is a problem, but the shifter feels more solid once the brass replacement is in place.
Fitment: 2015-2017 WRX without the STI short shifter; later compatibility depends on the installed shifter assembly.
PERRIN currently lists this standard stop for the 2015-2017 WRX without the STI short shifter and for certain later WRXs with an STI or upgraded shifter assembly. Match the stop to the shifter that is actually in the car, especially if a previous owner changed it. Check PERRIN’s current compatibility.
Fitment: Later VA and VB WRXs with the applicable factory shifter.
PERRIN now separates its standard and Super Shifter Stop versions by model year and shifter assembly. Use the current PERRIN instructions database to choose between the OEM, STI short-shifter, and PERRIN short-shifter versions.
The PERRIN solid shifter bushing replaces the rubber bushing at the transmission end of the shift cable with a brass piece that uses O-rings to retain some movement. It does not remove the side-to-side gate play handled by the shift stop. Instead, it gives the shift action a more solid, connected feel.
Access is from underneath the car: remove the plate below the shift cable, disconnect the cable end, replace the rubber bushing, and reassemble it with the supplied parts. PERRIN estimates about 30 minutes for installation. Read the current bushing specifications and instructions.
On our 2017 WRX, the brass bushing made the shifter feel more solid without introducing vibration. The stop still produced the more dramatic change because it removed so much lateral play.
Installing the PERRIN shift stop
The stop bolts to the shifter assembly inside the console and is easy to install. Leave the bolts loose, set the gaps, check that every gear engages cleanly, and tighten it down.
First, the bezel around the shifter that holds the shift boot is removed. Remove the shift knob by unscrewing it. Then, gently pull it up from the inner edges on the bezel and the plastic clips underneath will release. You can now remove the bezel and shift boot and set it aside.
Now remove the two 10mm bolts, pictured below, on top of the shifter assembly. These hold down a part that looks similar to the shift stop you’re installing, but it’s on the right side and is used for the reverse lockout.
Place the PERRIN shifter stop so it aligns with the holes for the bolts you just removed. Now, install the supplied bolts, but don’t tighten them fully yet. You’ll need to adjust the PERRIN shifter stop and the stock shift stop / reverse lockout.
Shift the car into 5th gear. Make sure the stock shifter stop on the right side has a very small gap. Shift into 6th gear and check it again. This is where the stock shift stop on the right side should sit, so that it guides the shifter into gear and doesn’t block it.
Repeat these steps for the left side with the PERRIN shifter stop. Put the car into first gear, and set the gap with the PERRIN shifter stop, then repeat with 2nd gear.
Repeat these steps until the shifter enters every gear cleanly and the stops leave only a small guide gap. Test every gate with the engine off and the clutch pedal depressed. Once the position is correct, tighten the hardware evenly. Too little clearance can make first or second difficult to select; too much leaves the play you are trying to remove.
The PERRIN shifter stop also includes washers for the two bolts on the left side of the shifter assembly. These help to reduce overall slop in the shifter, tightening everything up. Using a 7mm wrench, remove the nuts, taking care to not drop them. We recommend having a magnetic grabber on hand, and temporarily sticking a piece of cloth under the bolts as you work.
Install the supplied washers on the bolts, and then reinstall the nuts. Slowly tighten them, making sure to keep the washers centered under the nuts. Tighten them to remove the gap between the parts of the shift assembly.
Reinstall the shifter boot and knob, then check every gear again before driving. PERRIN calls for a post-install inspection. Our stop has remained in position without needing readjustment, but checking the hardware after the first drives is still sensible.
Is the shift stop or brass bushing the better first mod?
Install the shift stop first if you want the biggest and most immediate change. It is cheap, easy to install, and hugely reduced the side-to-side play on our car. The brass bushing is the next refinement: it may solve a feeling you did not notice until the new bushing makes each shift feel more solid. Together they make the VA WRX shifter feel more deliberate without requiring a short shifter or heavier shift knob.
Sources
- PERRIN standard WRX Shifter Stop - current fitment, materials, and installation estimate.
- PERRIN Super Shifter Stop for 2015-2017 WRX - current OEM-shifter version and adjustment design.
- PERRIN Solid Shifter Bushing - brass construction, O-rings, fitment, and installation instructions.