If your shifter feels vague between gears and the car rocks back and forth as you let the clutch out, the problem is not the shifter and it is not the clutch. It is the transmission mount. Subaru molds open voids into that bushing on purpose so drivetrain noise stays out of the cabin, and the trade is motion. The gearbox uses every bit of it. The OVERTAKE Transmission Mount Insert Kit is a molded 65A polyurethane insert that fills those voids and takes the free play out, with the factory mount staying right where it sits. Nothing gets pressed, nothing gets replaced, and nothing about it is permanent. Two part numbers cover the manual transmission Subaru lineup: A11047 for the three-void mount under the WRX, Impreza, Forester, Legacy, Outback, Baja, and Crosstrek, and A11048 for the two-void mount under the STI and the 2022 and newer WRX. Install runs 20 to 30 minutes with basic hand tools, and a packet of silicone lubricant ships in the box.
If you already know which one you need, the three-void kit for the WRX, Impreza, Forester, and Crosstrek is here, and the two-void kit for the STI and current WRX is here. For everyone else, here is what the factory mount is actually doing and why filling it changes how the car drives.
Why Does Your Subaru Shifter Feel Vague?
The transmission mount holds the tail of the gearbox to the crossmember through a rubber bushing. Subaru molds voids into that bushing, which is to say it leaves empty space in the rubber on purpose. Empty space lets the bushing deflect, and deflection is how drivetrain noise and vibration get absorbed before any of it reaches the floor of the cabin.
For a car that has to be livable on a commute, that is the right call. The cost of it shows up in two places every manual driver already knows about.
- Shifter slop. Move the lever and the gearbox moves too. Part of the input you put into the shifter goes into rocking the transmission rather than into the shift fork, so the gate feels vague and the engagement shows up a beat late.
- Clutch bucking. Let the clutch out, the driveline loads, the gearbox rotates against the mount, the load releases, and it rotates back. That oscillation is the shudder you feel trying to pull away smoothly.
Neither one is a defect. Both are the factory mount doing exactly the job it was engineered to do, and both trace back to the same few cubic inches of missing rubber.
What the OVERTAKE Insert Actually Does
The common answer to a sloppy transmission mount is to throw it away and bolt in a replacement with stiffer bushings. That works. It also runs into the hundreds of dollars, and it asks you to pull the mount out of the car to get there.
OVERTAKE came at it from the other direction. The play is not coming from the mount as an assembly, it is coming from the voids molded into the bushing. Fill the voids and the free motion goes away while the factory mount stays bolted exactly where it is. Nothing gets pressed, nothing gets replaced, and no new hardware goes into the car.
Why 65A Durometer and Not Something Harder?
Durometer was the real engineering decision here, and it is the reason this part is not simply a block of solid urethane.
A solid or near-solid mount pins the gearbox down and then hands you transmission whine straight through the floor, because there is nothing left in the path to absorb it. Anyone who has driven a car on solid mounts knows the sound. OVERTAKE landed on 65A because it keeps enough deflection in the system to stop that while still taking the slack out of the assembly.
The second reason is practical. 65A is soft enough to work into the mount by hand, which is what keeps this a driveway job instead of a shop visit. It is also molded in OVERTAKE blue to match the rest of the drivetrain lineup, which nobody but you will ever see and which still looks better than another gray lump under the car.
A11047 or A11048? Which Insert Fits Your Subaru
This is the part worth slowing down for, because the year ranges overlap and the answer is not the one you would guess from the model badge.
The difference is the mount itself. The factory transmission mount on the STI and on the current WRX carries two voids. The mount on the earlier WRX and across the rest of the manual Subaru lineup carries three. Same idea, different geometry, so the inserts are molded separately rather than one part trimmed down to cover both.
The short version: if you drive an STI of any year, or a WRX from 2022 on, you want A11048. Everything else manual takes A11047. A 2015 WRX and a 2015 STI do not take the same part.
A11047 Fitment, Three-Void Mount
- Subaru WRX - 2002 through 2021
- Subaru Impreza - 1998 through 2023
- Subaru Forester - 1998 through 2018
- Subaru Forester XT - 2004 through 2008
- Subaru Crosstrek - 2013 through 2023
- Subaru Legacy - 1997 through 2009
- Subaru Legacy GT - 2005 through 2009
- Subaru Outback - 2000 through 2009
- Subaru Outback XT - 2005 through 2009
- Subaru Baja - 2003 through 2006
A11048 Fitment, Two-Void Mount
- Subaru WRX STI - 2004 through 2021
- Subaru WRX - 2022 through 2026
Manual transmission only, both part numbers. There is no automatic or CVT fitment for either insert.
How Long Does the Install Take?
Plan on 20 to 30 minutes with basic hand tools. There is nothing in this job that needs a press, a shop, or a Subaru specific tool.
The insert works into the voids of the factory mount, and a packet of silicone lubricant ships in the box so the polyurethane slides in without tearing on the edges of the bushing. That lube is not optional, and it is the difference between a clean install and a torn insert.
None of it is permanent either. If you decide you want the factory ride quality back, the insert comes back out and the mount is untouched.
Who Should Buy This?
This one lands differently depending on what your car is for.
If you daily a manual Subaru and the shifter has always felt a little disconnected, this is the cheapest meaningful fix available to you. No tune, no shop, nothing to undo at trade-in time.
If you autocross or run track days, the value is in how the car behaves under load. Every time you get on and off the throttle the gearbox is moving against that mount. Taking the motion out means the shift you ask for is the shift you get, at the moment you asked for it.
If you already put in a short shifter and came away underwhelmed, read this part twice. A short throw shifter shortens the lever. It does nothing about the gearbox moving underneath it, and slop in the mount will show up through any shifter you bolt in. The two parts solve different halves of the same complaint.
If your Subaru is your quiet commuter and you like it exactly that way, be honest with yourself before you order. OVERTAKE chose 65A specifically to keep transmission whine out of the cabin rather than going harder, but a mount with the voids filled is still a stiffer mount than the one Subaru shipped you.
Ready to Take the Slop Out of Your Drivetrain?
Two part numbers, one job. Pick up the three-void kit if you are in a WRX through 2021, an Impreza, a Forester, a Legacy, an Outback, a Baja, or a Crosstrek. Grab the two-void kit if you are in an STI or a 2022 and newer WRX.
Frequently Asked Questions
Will this fit my 2022 WRX?
Yes, with A11048. The current WRX uses the same two-void transmission mount as the STI, so the 2022 through 2026 cars take the STI insert rather than the one built for the older WRX. It is the one piece of the fitment that catches people out.
I have a 2015 WRX and my friend has a 2015 STI. Same part?
No. Same model year, different mount. The 2015 WRX takes A11047 with the three-void insert. The 2015 STI takes A11048 with the two-void insert. Go by the mount under the car, not by the year on the title.
Does this fit an automatic or CVT Subaru?
No. Both kits are built around the manual transmission mount, and there is no automatic or CVT fitment for either part number.
Will this make my car louder or harsher inside?
Filling the voids makes the mount stiffer than stock, and a stiffer mount passes more of what the drivetrain is doing into the car. That is the entire mechanism. OVERTAKE picked 65A rather than a harder urethane or a solid mount specifically so that transmission whine does not come along with the tighter feel. If you decide you want the factory isolation back, the insert comes out.
I already have a short shifter. Is this redundant?
No, and it is a common reason people end up disappointed with a short shifter. Shortening the lever changes how far your hand moves. It does not stop the gearbox from rocking on its mount, which is where the vague feeling in the gate comes from. The two upgrades address different halves of the same complaint and they work well together.
