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Complete CURT Class 3 2" trailer hitch and 5-flat wiring kit (with 4-way to 5-way adapter for surge brakes) engineered for the 1988 - 2000 GMC C3500 With 10" step bumper. Vehicle-specific fit, plug-and-play installation, all hardware and instructions included.
This custom kit fits the following vehicles:
All Hardware and Installation Instructions Included!
Whatever your task at hand -- whether it's launching that boat before daybreak, setting up your camper before the rush or getting a final load to the dump before close -- CURT class 3 trailer hitches offer the strength needed for serious towing. They make it easy to hitch up and Bring It, offering a vehicle-specific fit and the weight capacity to handle a variety of trailers. Custom class 3 hitches are the most common type of receiver hitch for pickup trucks and SUVs. Because of their weight range, they are also found on full-size cars, crossovers and minivans. Each custom-fit class 3 hitch package is made for vehicle-specific mounting. This particular kit fits older years of Ford, GMC and Chevy pickup trucks (see application info to verify vehicle compatibility). It provides a weight carrying capacity of 6,000 lbs. GTW and 600 lbs. TW. It is also compatible with a weight distribution hitch for level towing and a rating of 10,000 lbs. WD and 1,000 lbs. WDTW. CURT class 3 trailer hitches are typically used to attach and haul utility trailers, boat trailers, campers, snowmobile or ATV haulers and more (NOTE: Never exceed the lowest-rated towing component). Each class 3 hitch has a 2" receiver tube and is tested in accordance with SAE J684 for safety. To ensure that CURT class 3 receiver hitches have what it takes for serious trailering, they are designed using a hands-on approach and are constructed with rugged, high-strength steel and precise welding. We also protect our class 3 hitches in a co-cured finish of liquid A-coat and black powder coat for superior resistance to rust, chipping and UV damage.
If your vehicle is not equipped with wiring for towing a trailer, CURT custom wiring is the ideal solution. A custom wiring harness -- also called a T-connector -- is a simple, plug-and-play electrical device that plugs into your automotive electric system and provides a standard, universal trailer wiring connection. This is done using two or more vehicle-specific, OEM-compatible connectors to plug into the taillight assembly, eliminating the need for cutting, splicing and soldering during installation. Custom wiring harnesses are made vehicle-specific, and while they are not available for all vehicles, they do offer one of the fastest, easiest and most secure ways to wire a vehicle for towing. This particular plug-in harness provides a 4-way flat connector socket and is designed to be a custom wiring harness to fit certain years of the GMC C1500, C2500, C3500, K1500, K2500 and K3500 (to verify your vehicle compatibility, see application info). It comes with all necessary wiring components to establish a reliable trailer wiring connection, as well as a dust cover to keep the connector clean when not in use. You have a picture in mind of your next destination -- maybe it's the boat landing at your favorite fishing spot, maybe it's a campsite that overlooks one of nature's masterpieces, or maybe it's the next big jobsite. However, turning that picture into a reality takes more than just daydreaming. It takes a solid connection and the right amount of power. CURT custom wiring is made with some of the most sophisticated technology in the industry and is designed to install with ease, giving you a long-lasting electrical connection for your towing hitch setup.
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 888-634-94941 compatible vehicles
| Year | Make & Model | Notes |
|---|---|---|
| 1988 - 2000 | GMC C3500 | With 10" step bumper |
Yes, the 88 - 00 GMC C3500 With 10" step bumper Curt 2" Class 3 Trailer Tow Hitch + 5-Flat Wiring Kit Tow Boat/Utility Trailer with Surge Brakes 13099 (Part #5W-CHW-1378) is designed to fit the 1988-2000 GMC C3500.
The 88 - 00 GMC C3500 With 10" step bumper Curt 2" Class 3 Trailer Tow Hitch + 5-Flat Wiring Kit Tow Boat/Utility Trailer with Surge Brakes 13099 (Part #5W-CHW-1378) fits 1988-2000 GMC C3500 models. The 2000 model year is the last year covered by this part number. For newer models, check for an updated version.
The 88 - 00 GMC C3500 With 10" step bumper Curt 2" Class 3 Trailer Tow Hitch + 5-Flat Wiring Kit Tow Boat/Utility Trailer with Surge Brakes 13099 (Part #5W-CHW-1378) fits the following vehicles: 1988-2000 GMC C3500. Always verify your specific year, make, and model before ordering.
The 88 - 00 GMC C3500 With 10" step bumper Curt 2" Class 3 Trailer Tow Hitch + 5-Flat Wiring Kit Tow Boat/Utility Trailer with Surge Brakes 13099 (Part #5W-CHW-1378) Refer to the included instructions for installation details. Basic hand tools are typically all you need.
Yes, part number 13099 is designed for 1963–1996 Ford Trucks (all full size, old body style only). Your 1985 F-150 is within this range and should be compatible.
Yes, part number 13099 is compatible with 1970–2000 Chevrolet & GMC Pickup (full size with 10" step bumper). Your 1995 C1500 is within this range, provided it has a full-size frame and a 10" step bumper.
No. Part number 13099 is designed only for 1963–1996 Ford Trucks (all full size, old body style only). It is not compatible with Ford trucks manufactured after 1996.
The manual specifies compatibility with 1970–2000 Chevrolet & GMC Pickup (full size with 10" step bumper). If your vehicle does not have a 10" step bumper, compatibility is not confirmed by the manual. Contact Curt Manufacturing or a fitment specialist to verify.
The kit includes: 6× 1/2–13 UNC carriage bolts, 1–3/4" long (part 10-10272); 6× 0.250 × 1.50 × 2.00" square hole spacers (CM-SP1); 6× 1/2–13 UNC serrated flange nuts (part 20-00062); 8× 7/16–14 UNC serrated flange nuts (part 20-00103); and 8× 7/16–14 UNC carriage bolts, 1–1/2" long (part 10-10282).
Yes. Step 1 of the installation instructions requires you to remove the spare tire from the vehicle before beginning installation. Note that the spare tire carrier may need to be relocated and/or modified to retain under-vehicle tire stowage after the hitch is installed. On some Ford Pickup models with a 16" spare tire, the spare tire cradle may also require adjustment.
Yes. Step 2 requires you to measure the vehicle frame width. The bracket orientation depends on frame width: for 34" frames, position the side bracket with mounting flanges pointing inboard; for 38" frames, position the bracket with mounting flanges pointing outboard.
Yes, drilling is required. Step 4 requires you to drill six 17/32" diameter holes in the vehicle frame using the slotted holes in the bracket as a guide. The manual recommends starting with a smaller bit and working up to 17/32". In some cases, it may be possible to use existing holes in the frame instead of drilling new ones.
Drill six 17/32" diameter holes in the vehicle frame. The manual recommends starting with a smaller bit and working up to 17/32" to ensure accuracy. Use the slotted holes in the bracket as a guide for hole placement.
Torque all 1/2" fasteners to 110 lb.-ft. and all 7/16" fasteners to 70 lb.-ft. These torque values are applied after the crosstube assembly is installed into the side brackets and all fasteners are hand-tightened.
No. Step 5 instructs you to install the side bracket mounting fasteners but explicitly states "Do not tighten at this time." The fasteners are tightened to final torque (110 lb.-ft. for 1/2" fasteners) only after the crosstube assembly is installed and all fasteners are in place (Step 7).
The crosstube assembly is attached using 7/16" × 1–1/2" carriage bolts and 7/16" serrated flange nuts (part 20-00103). Eight of each fastener are included in the kit. These fasteners are torqued to 70 lb.-ft. after installation.
The six 0.250 × 1.50 × 2.00" square hole spacers (part CM-SP1) are installed inside the vehicle frame when mounting the side brackets. They are placed between the frame and the bracket mounting fasteners to ensure proper spacing and load distribution.
Do not exceed your vehicle manufacturer's recommended towing capacity. The hitch has its own capacity ratings (weight-carrying and weight-distribution modes), but the manual emphasizes that the vehicle's limit takes precedence. Consult your vehicle's owner manual for the maximum towing capacity.
Periodically check the receiver hitch to ensure that all fasteners are tight and that all structural components are sound. The manual does not specify an exact interval, but regular inspection before towing is recommended to maintain safety and warranty coverage.
1963–1996 Ford Trucks (all full size, old body style only) and 1970–2000 Chevrolet & GMC Pickup (full size with 10" step bumper).
Yes. You must drill six 17/32" diameter holes in the vehicle frame. The manual recommends starting with a smaller bit and working up to 17/32". Existing frame holes may be reused if available.
Six 1/2–13 UNC carriage bolts, six square hole spacers, six 1/2–13 UNC flange nuts, eight 7/16–14 UNC flange nuts, and eight 7/16–14 UNC carriage bolts.
Torque all 1/2" fasteners to 110 lb.-ft. and all 7/16" fasteners to 70 lb.-ft.
Periodically check all fasteners to ensure they are tight and inspect all structural components for soundness.
Yes, the Curt 55315 custom wiring harness is designed for Chevrolet C/K 1500 pickup trucks. It is also compatible with Chevrolet C/K 2500/3500, GMC C/K 1500, and GMC C/K 2500/3500 pickup trucks. The harness connects to your vehicle's existing taillight wiring harness connector.
Yes, the Curt 55315 custom wiring harness is compatible with GMC C/K 2500/3500 pickup trucks, as well as GMC C/K 1500 models. The installation process is the same across all listed applications.
The Curt 55315 kit includes a custom wiring harness with a yellow wire connector end, a white ground wire with ring terminal, a provided screw for grounding, cable ties for securing loose wires, and a 4-flat dust cover to help prevent corrosion.
The manual lists no specific tools as required. However, you will need a drill to create a 3/32" pilot hole for the ground wire screw if a suitable existing screw with nut is not available on the vehicle frame. A test light or properly wired trailer is needed to test for proper function after installation.
The manual does not specify whether the battery must be disconnected. Check your vehicle owner's manual or contact the vehicle manufacturer for guidance on electrical work preparation.
Locate your vehicle's taillight wiring harness connector. Separate the connector from the taillight housing carefully, taking care not to damage the locking tabs. Insert the custom wiring harness end with the yellow wire between the separated connectors. Push both connectors fully together until the locking tabs are in place and secure.
Locate a suitable grounding point near the taillight connector, such as an existing screw with nut in the vehicle frame. The area must be free of rust, dirt and paint. If no suitable point exists, drill a 3/32" pilot hole and use the provided screw. Secure the white ground wire using the ring terminal and the provided screw.
Drilling is required only if a suitable existing screw with nut is not available on the vehicle frame near the taillight connector for grounding. If drilling is necessary, you will drill a 3/32" pilot hole. Before drilling, check for miscellaneous items that may be hidden behind or under any surface to avoid damage and personal injury.
When in use, route the 4-flat connector to the center of the vehicle and out of the trunk. When not in use, roll up the connector and store it in a convenient, out-of-the-way location inside the trunk. Secure any loose wires with the provided cable ties.
Test for proper function by using a test light or connecting a properly wired trailer to the 4-flat connector. All steps must be followed to ensure the wiring harness will function properly. If testing reveals issues, review the installation steps to confirm all connections are secure and the ground wire is properly attached.
Do not exceed the product rating or your tow vehicle's lamp load rating, whichever is lower. Exceeding the product rating can cause loss of warranty, overheating and potential fire. Refer to your vehicle owner's manual or contact the vehicle manufacturer for your specific lamp load rating.
Install the provided 4-flat dust cover to help prevent corrosion. This should be done as part of the final installation step after all other components are in place.
No, you do not need to remove the taillight housing. You only need to separate the taillight wiring harness connector from the housing by carefully disconnecting it, taking care not to damage the locking tabs. The custom harness is then inserted between the separated connectors.
Yes, if you have a Chevrolet or GMC C/K 1500, 2500, or 3500 pickup truck. The harness connects to your vehicle's existing taillight connector.
A drill may be needed to create a 3/32" pilot hole for the ground wire screw if no suitable existing screw is available on the vehicle frame. A test light or properly wired trailer is required to test the installation.
Drilling is only required if no suitable existing screw with nut is available on the vehicle frame near the taillight connector. If drilling is necessary, drill a 3/32" pilot hole. Always check for hidden items before drilling.
Do not exceed the product rating or your vehicle's lamp load rating, whichever is lower. Exceeding the rating can cause loss of warranty, overheating and potential fire.
Test for proper function using a test light or by connecting a properly wired trailer to the 4-flat connector.
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