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2026 Subaru Forester
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Always the correct part
We know our products
Quality Products
Free Shipping!
Vehicle battery connection required
Warranty: One-Year Limited Warranty
Electrical System Type: 3W
Output Type: 4-Way Flat
Tail Light Circuits: 6.0 Amps
Turn and Brake Circuits: 3.0 Amps
Installation Difficulty: Novice
Installation Time Exact (Minutes): 10
CURT custom wiring connectors are the easiest way to outfit your vehicle with a CURT trailer wiring connection. They are built with some of the most advanced technology in the industry, and each one is custom-fitted to work with a specific make and model. Some automotive manufacturers install a special socket on the vehicle to be used for vehicle-to-trailer wiring. Although this special socket is not equipped on every vehicle, a CURT custom wiring connector -- also called a T-connector -- utilizes the socket for simple, stress-free installation. Rather than requiring you to cut, splice and solder into your vehicle's wiring system, the custom wiring connector uses a single OEM-compatible plug and instantly provides a standard, universal vehicle-to-trailer wiring connection, typically in the form a 4-way flat. All CURT custom wiring connectors are made vehicle-specific for the easiest possible installation and the best fit. This particular plug-in connector provides a 4-way flat socket and is designed to be a custom wiring option for certain years of the Subaru Ascent, Forester, Outback, Crosstrek and XV Crosstrek (to verify your vehicle compatibility, see application info). It comes with all necessary hardware to establish a solid connection. It also comes with a dust cover to keep the connector socket clean when not in use. To ensure long-lasting reliability, all CURT custom wiring connectors are thoroughly tested for optimal functionality. Stress is the last thing you should feel when towing a trailer -- whether you're hauling your RV to that favorite camping destination, your ATVs up to the hunting grounds or your fishing boat to the new hidden hotspot. At CURT, we think your towing equipment should add to the enjoyment of your experience, not detract from it.

CURT offers a variety of high-quality trailer hitches and accessories for select vehicle models. Find the perfect fit for your towing needs at TowUniverse.
CURT, a Lippert brand, offers a complete line of towing products and is the leading manufacturer of custom-fit trailer hitches. We offer the broadest selection of custom-fit hitches, and each one is designed, welded, and coated in Wisconsin.
CURT is also a leader in flat towing products, as well as 5th wheel, gooseneck, and weight distribution hitches, ball mounts, electrical components, cargo solutions, and other towing accessories.
For everything from passenger cars and vans to full-size pickups and SUVs, CURT is 'The First Name in Towing Products®.'
Experts available to answer your questions
Call 888-634-9494One-Year Limited Warranty
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6 compatible vehicles
| Year | Make & Model | Notes |
|---|---|---|
| 2019 - 2026 | Subaru Ascent | Installation Time: 30-60 minutes |
| 2016 - 2026 | Subaru Crosstrek | Installation Time: 30-60 minutes |
| 2026 | Subaru Forester | — |
| 2009 - 2025 | Subaru Forester | Installation Time: 30-60 minutes |
| 2010 - 2025 | Subaru Outback | Installation Time: 30-60 minutes |
| 2013 - 2015 | Subaru XV Crosstrek | Installation Time: 30-60 minutes |
The CURT Custom 4-Flat, Select Subaru Vehicles, OEM Tow Package Required Trailer Connector Kit (Part #BKDK56040) fits the following vehicles: 2019-2026 Subaru Ascent; 2016-2026 Subaru Crosstrek; 2009-2026 Subaru Forester; 2010-2025 Subaru Outback; 2013-2015 Subaru XV Crosstrek. Always verify your specific year, make, and model before ordering.
Yes, the CURT Custom 4-Flat, Select Subaru Vehicles, OEM Tow Package Required Trailer Connector Kit (Part #BKDK56040) is designed to fit the 2019-2026 Subaru Ascent.
The CURT Custom 4-Flat, Select Subaru Vehicles, OEM Tow Package Required Trailer Connector Kit (Part #BKDK56040) fits 2019-2026 Subaru Ascent models. The 2026 model year is the last year covered by this part number. For newer models, check for an updated version.
The CURT Custom 4-Flat, Select Subaru Vehicles, OEM Tow Package Required Trailer Connector Kit (Part #BKDK56040) Typical installation time is 30-60 minutes. Basic hand tools are typically all you need.
Yes, the Curt 56040 vehicle-to-trailer connector fits Subaru Forester models from 2009 onwards, including 2009–2013 and 2014+ versions. However, the wiring harness location differs between these model years, so follow the instructions specific to your year. The connector does not fit Subaru Crosstrek or XV Crosstrek Hybrid models.
No. The Curt 56040 is designed for Subaru Crosstrek and XV Crosstrek models, but explicitly excludes Hybrid versions. If you have a Hybrid model, contact Curt Manufacturing or your vehicle manufacturer to confirm compatibility.
The Curt 56040 is rated for Signal Circuits at 3.0 amps per side and Tail/Running Circuits at 6.0 amps total. The battery connection must be fuse-protected with a 10-amp maximum fuse. Do not exceed the product rating or your tow vehicle's lamp load rating, whichever is lower, as exceeding it can cause loss of warranty, overheating and potential fire.
You will need a 10mm socket, a ratchet, and a panel trim removal tool. These are the only tools specified in the manual. Additional tools such as a drill may be needed if you must drill a pilot hole for the ground screw, depending on whether a suitable existing screw is available in your vehicle.
Yes. The first step of installation is to locate the vehicle battery on the driver side under the hood and disconnect the negative battery terminal. This must be done before proceeding with any other installation steps.
On 2009–2013 Forester models, the vehicle wiring harness connectors are located on the driver side under the trays in the trunk. You must first remove all trunk floor coverings and the plastic fasteners securing the trays in the center and on the driver side to access them.
On Subaru Outback models, the vehicle wiring harness connectors are tucked up behind the driver side inner fender trim, visible near the rubber grommet in the floor and the cargo anchor. You must first remove trunk floor coverings and trays to access this area.
On 2014+ Forester and XV Crosstrek models, the vehicle taillight wiring harness connectors are located on the driver side behind the rear trim panel. Pull back on the rear trim panel to locate them.
Insert the custom connector end into the vehicle connector. Make sure the connectors are fully inserted with locking tabs in place. Do not proceed until the connection is secure and the locking tabs are engaged.
Not necessarily. First, locate a suitable grounding point near the connector, such as an existing screw with nut in the vehicle frame. If no suitable existing screw is available, you may drill a 3/32" pilot hole for the provided screw. Before drilling, check for miscellaneous items that may be hidden behind or under any surface to avoid damage and personal injury.
Locate a suitable grounding point near the connector, such as an existing screw with nut in the vehicle frame, or drill a 3/32" pilot hole for the provided screw if needed. The area should be free of rust, dirt and paint. Secure the white ground wire using the ring terminal and provided screw.
Locate a flat spot inside the vehicle, near the taillight, and adhere the black converter box using the provided double-sided tape. Ensure the surface is clean and flat to allow the tape to bond securely.
Install a red 10-amp fuse into the in-line fuse holder. This is the maximum fuse rating allowed; do not use a fuse with a higher amperage rating.
When in use, route the 4-flat to the center of the vehicle. When not in use, roll it up and store in a convenient, out-of-the-way location. Secure any loose wires with the provided cable ties to prevent tangling and damage.
After installation, reinstall all items removed during the install and reconnect the negative battery terminal. Install the provided 4-flat dust cover to help prevent corrosion. Test the connector for proper function by using a test light or connecting a properly wired trailer.
Test the connector for proper function by using a test light or connecting a properly wired trailer. All steps must be followed to ensure the wiring connector will function properly.
Yes, the Curt 56040 fits Subaru Ascent, Forester (all years), Outback, Crosstrek, and XV Crosstrek—but excludes Hybrid models. Confirm your model year and drivetrain before purchasing.
You need a 10mm socket, ratchet, and panel trim removal tool. A drill may be needed if no existing ground screw is available.
Yes, disconnect the negative battery terminal before starting installation.
Drilling is not required if an existing screw with nut is available in the vehicle frame for the ground connection. If not, drill a 3/32" pilot hole for the provided screw.
The maximum fuse rating is 10 amps. Do not exceed this rating or the tow vehicle's lamp load rating, whichever is lower.
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