Towing a trailer behind your full-size van just got simpler. The CURT 55540 is a vehicle-specific T-connector harness engineered to plug directly into the factory taillight wiring on 2003-2009 Chevrolet Express and GMC Savana vans -- no wire cutting, no splicing, no guesswork. Install in minutes and get reliable 4-flat trailer lighting output every time.
CURT's custom-fit wiring harnesses are designed to match the exact connector configuration of your vehicle's OEM taillight plugs. The 55540 uses a T-connector design -- it loops between the factory taillight sockets and the vehicle harness, so your van's lights continue to work normally while a standard 4-flat output is made available for any trailer equipped with a 4-pin flat connector.
This is the correct solution for full-size van owners who need to tow utility trailers, camper trailers, boat trailers, cargo trailers, or any flat-four-equipped trailer. It works with the factory wiring without voiding electrical warranties or creating hard-to-trace shorts caused by improper splicing.
Engineered specifically for 2003-2009 Chevy Express and GMC Savana full-size vans. Plugs directly into OEM taillight connectors with no modification.
Delivers standard 4-flat (4-pin flat) trailer connector output -- left turn/brake, right turn/brake, tail, and ground -- compatible with the vast majority of light-duty trailers.
Loops into existing factory wiring without cutting or splicing. Vehicle taillights remain fully functional. Unplug the harness and no trace remains.
At just 0.63 lbs and packaged at 9 x 4 x 3 inches, this harness tucks away cleanly behind the rear bumper area when not in use.
Universal wiring kits require you to identify and cut into your vehicle's existing wiring, then connect each wire by color -- a process that can introduce corrosion points, mismatched wire gauges, and warranty concerns. CURT's vehicle-specific harnesses eliminate all of that. The 55540's connectors are molded to match the exact OEM plugs on 2003-2009 Express and Savana taillights, so the install is a matter of unplugging the factory connector, inserting the T-harness, and routing the output pigtail toward the hitch receiver.
This approach also preserves the factory system's current-draw profile. Because it does not tap directly into the wiring, it is compatible with the factory's multiplexed or non-multiplexed taillight circuits without triggering bulb-out warnings on vehicles that monitor circuit load.
Verify your model year and trim before ordering. Certain specialty upfit or cutaway variants may use non-standard wiring configurations -- inspect your factory taillight connectors to confirm OEM plug style matches.
The 4-flat (also called 4-pin flat) connector supports left turn/brake, right turn/brake, running/tail lights, and ground. This covers the lighting requirements for most utility trailers, boat trailers, PWC trailers, single-axle cargo trailers, pop-up camper trailers, and small travel trailers. If your trailer also requires electric brakes or a 12V auxiliary charge circuit, you will need a 5-flat or 7-way connector -- the 55540 does not support those functions.
No special tools are required beyond basic hand tools for accessing the rear taillight area. The general process:
For a complete towing setup on your 2003-2009 Express or Savana, CURT also manufactures vehicle-specific receiver hitches for these vans. Matching your hitch and wiring from the same brand ensures consistent fitment and a clean professional install.