Installing 7-Way and 4-Way Connectors on a 2015 GMC Acadia
Question:
I have a wiring harness pre installed. And ordered a HM40975. Jon G suggested part 118271 to connect the 2. My question is, will part #118271 run the 7 pole and the 4 flat on part HM40975? Or just the 7 pole? Thank you.
asked by: Nathan S
Helpful Expert Reply:
The Hopkins # HM40975 that you referenced plugs into a US Car Connector (see attached picture). This typically will replace a factory 7-Way on a vehicle so if your 2015 GMC Acadia didn't come with a 7-Way you might not have that connector. If it does exist though it will be located somewhere around the trailer hitch.
If you don't have the US Car Connector but you would like fully functioning 7-Way and 4-Way connectors then we do have a solution for you. Simpy install the T-One Vehicle Wiring Harness # 118271 (if you have the factory tow package) and then swap out the included connector with the Hopkins # HM40975 that you referenced. To keep from drilling into your vehicle or trailer hitch use the No-Drill Mount Bracket # 18140 as well.
Attached are some installation videos for you to check out.

Products Referenced in This Question
T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- Factory Tow Package
- 7 Round - Blade
- Plug and Lead
- Plug-In
- Visible
- Tekonsha
more information >
No-Drill Mount for Electrical Mounting Bracket - Short
- Accessories and Parts
- Trailer Wiring
- Mounting Hardware
- Brackets
- 4 Flat
- 5 Flat
- 4 Round
- 5 Round
- Tow Ready
more information >
Product Page this Question was Asked From
7- and 4-Pole Trailer Connector Socket w/ Mounting Bracket - Vehicle End
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- No Tow Package
- 7 Round - Blade
- 4 Flat
- Plug Only
- Hopkins
more information >
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Nathan S.
6/7/2018
I have a wiring harness pre installed. And ordered a HM40975. Jon G suggested part 118271 to connect the 2. My question is, will part #118271 run the 7 pole and the 4 flat on part HM40975? Or just the 7 pole? Thank you.