WARNING
Under no circumstances should you drill into the frame or underbody of your Subaru Ascent to install an aftermarket or commercial trailer hitch.
Such actions may allow harmful substances such as exhaust gases, water, or road debris to penetrate the passenger compartment through the created openings. Exhaust gases contain carbon monoxide, an invisible and odorless substance that can pose a serious health risk or even be fatal when inhaled.
Additionally, altering the structural integrity of the Subaru Ascent by drilling into the frame or underbody can weaken critical components and accelerate corrosion around the modified areas, reducing long-term durability and safety.
CAUTION
- Never alter or interfere with the exhaust system, braking components, or any other essential systems of the Subaru Ascent when installing towing equipment.
- Avoid using axle-mounted trailer hitches, as they may cause severe damage to the axle housing, wheel bearings, tires, and suspension components.
For optimal safety and compatibility, always use a genuine Subaru Ascent trailer hitch specifically designed for your vehicle. Genuine components are engineered to match factory specifications and can be obtained through an authorized SUBARU dealer.
When you do not tow a trailer
CAUTION
- Keep the hitch receiver clean and free from dirt, moisture, and corrosion.
Maintenance should be limited to wiping the surfaces with a clean cloth.
Application of grease, oil, or other lubricants is not recommended, as it may attract debris and accelerate wear.
- When the hitch ball is removed, always install the protective plastic insert and/or bumper cover to shield the receiver from contamination and damage.
When not in use, protect the hitch ball with a cap and store it securely to prevent damage or loss.
Connecting a trailer
Trailer brakes
WARNING
- Trailers with a combined weight exceeding 1,000 lbs (453 kg) must be equipped with their own braking system when towing with the Subaru Ascent.
- Never attempt to directly connect the trailer’s hydraulic braking system to the hydraulic brake system of the Subaru Ascent, as this can severely compromise braking performance and lead to hazardous situations.
If your trailer surpasses the specified weight threshold, it must include an independent braking system. Electric or surge-type brakes are strongly recommended, provided they are installed correctly and meet all applicable standards.
Ensure that your trailer’s braking system complies with all relevant local, state, and federal regulations. The braking system of the Subaru Ascent is not designed to integrate directly with trailer hydraulics, so professional installation guidance from a SUBARU dealer or trailer specialist is essential.
Trailer safety chains
WARNING
Always secure the trailer to your Subaru Ascent using properly rated safety chains. Failing to do so can create a dangerous situation if the trailer detaches from the hitch.
In the event of hitch or coupling failure, safety chains act as a backup connection to prevent the trailer from separating completely and causing a road hazard.
For proper installation, attach two chains—one on each side of the trailer tongue—and cross them beneath the tongue. This configuration helps support the trailer and prevents it from striking the ground if disconnection occurs.
Allow enough slack in the chains to accommodate turning maneuvers, but ensure they do not drag on the road surface.
Side mirrors

After attaching a trailer to your Subaru Ascent, verify that the standard side mirrors provide adequate rearward visibility. If blind spots increase significantly, install extended towing mirrors that comply with applicable regulations to ensure safe lane changes and maneuvering.
Trailer lights
CAUTION
Improper wiring or direct splicing of trailer lights into the Subaru Ascent electrical system can lead to damage or malfunction of the vehicle’s lighting system.
Correct trailer light integration requires modification of the electrical circuit to handle additional load demands. For proper installation, always consult a SUBARU dealer or qualified technician.
Each time a trailer is connected, test all lighting functions—including brake lights, turn signals, and running lights—to ensure proper operation.
Tires
WARNING
Never tow a trailer using a temporary spare tire on your Subaru Ascent.
Temporary spare tires are not engineered to withstand towing loads and may fail under stress, leading to reduced vehicle stability and potential accidents.
Always ensure that both the Subaru Ascent tires and trailer tires meet the manufacturer’s specifications for size, load capacity, and inflation pressure.
If a tire failure occurs while towing, seek assistance from a professional roadside service provider. Avoid attempting temporary repairs that could compromise safety.
If carrying a full-size spare tire in your Subaru Ascent or trailer, make sure it is properly secured to prevent movement during travel.
Additional note: Proper installation and use of towing equipment with the Subaru Ascent significantly enhance driving safety, stability, and reliability. Always prioritize certified components and follow recommended procedures to ensure optimal towing performance.
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WARNING
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