If you read the entire post from 2015 WRX and STI Exposed article, you would know that the 2015 WRX shifter is one of the things that I feel is terrible about the car. Normally cars that use cable shifters have a very positive feel and provide excellent feedback, but that is not the case for the 2015 WRX.
This all started the first day I drove the car for an extended period of time. I first hated how the shifter felt regarding the distance between gates. It felt like 1/2 gate was really far away from 3/4 gate. Then 5/6 gate was really close to 3/4 gate. This led me to dig into the shifter more and figure out why this is happening. What I discovered was that the shifter is really sloppy feeling when its in gears 1 and 2 and really tight in the 3rd, 4th, 5th and 6th. This gives you the false feeling of the gates being weird. So how can we fix this slop? Easy……
The PERRIN Shifter Stop is the first of its kind for PERRIN as well as any Subaru. This wasn’t something we ever NEEDED to design before since the transmissions generally shifted really well. If you are a past Suby owner, you a probably wondering how sloppy the WRX shifter is, if you are going to notice this, and then how does this thing work. All good questions, and to be answered below.
How Sloppy Is The WRX Shifter?
Using the diagram below, you can see that there is a huge amount of slop in the 1st/2nd gate compared to the others. These measurements are taken in gear at the end of the knob and with very light action moving it left to right. You can add about .25″ to the below numbers if you push on it left to right with a bit more force. The 1st/2nd gate is so sloppy that it almost feels like its in neutral on a normal car, so when this slop is removed, its amazingly different. Almost to the point of making the car shift as good as the 6spd STI tranny.
After installing the PERRIN Shifter Stop, you can see how much this tightens up the slop. Going from 1.00″ of loose sloppy feeling in 1st and 2nd, to .12″ is very noticeable. Even people that have never driven the WRX notice how much better this feels just sitting in the car.
How Does This Part Work?
As you can see from the above diagram, there is a varying amount of slop in each gate. The PERRIN Shifter Stop only fixes the slop found in 1st/2nd gate. 3rd/4th gate is already very good because the internal parts of the transmission have very little slop in them. The 5th/6th gate changes because we have you adjust the OEM shifter stop to help tighten things up a little. The OEM shifter stop is mainly used for locking out reverse, but doubles as a shifter stop, lucky for us that it is adjustable!
You can see the OEM shifter mechanism above and how the PERRIN Shift Stop is similar to the OEM part but for the other side. When you place the transmission into 1st or 2nd gear, the shifter has nothing for it to rest against, so the play that exists inside the transmission (shift forks, syncros and rods) all gets translated to the shifter. In this case it’s more than 1″ of free play!
The PERRIN Shift Stop creates a physical stop on the shifter to shift rod mechanism, this controls the amount of slop translated from the tranny to the shifter. When properly adjusted, the amount of free play goes from 1.00″ to about .10″. Not to mention, the feeling of putting the transmission into 1st, or downshifting into 2nd is significantly improved and feels much more solid.
Besides removing the slop found in 1st and 2nd, you will find going from 2nd to 3rd and 5th to 4th is much more natural feeling and much more positive as the slop doesn’t translate into the sort of lost feeling of which gear you are in. One complaint I had before was the distance from gate to gate being different, and that completely goes away after installing the PERRIN Shift Stop.
This part is like many of our other shifter bushings an short shifters, once it’s installed you will wonder why Subaru didn’t just make it like this to start with.
Bonus Fix Included
Another thing I found while coming up with this part is the whole shifter mechanism moves around a bunch as well. The biggest culprit of this is the gap you can see in the below picture. Like with everything, there is a tolerance in what something is made to. In this case, the tolerance between the shifter mechanism parts is pretty large. You would think that the OEM bolts would suck this close, but they do not because they are a shoulder bolt. When they are tightened down they do not actually suck things together. We include some special SS washers that allow this gap to be closed up when the nuts are tightened. This tiny amount of flex translates into a much larger amount of flex the top of shift knob.
One of my favorite things about modifying cars is improving the way they feel and this part is a perfect example that. It makes such a huge improvement and is so noticeable, that it will bring new joy to your driving experience. This will be a mod that everyone will want and everyone can afford. Add the also affordable PERRIN shifter bushing to this same installation and you will be very pleased with the way your 2015 WRX shifts. This doesn’t only apply to 2015 WRX customers, but also 2010-14 Legacy/Outback with manual tranny, and 2014+Forester with Manual tranny.