How to Install a Trailer Brake Controller on a 1998 GMC C/K Series Truck

Updated 09/19/2012 | Published 09/16/2012

Products Featured in This Question

Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers

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$57.20

Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires

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$118.67

Question:

I have a 1998 gmc truck cant find wires under dash too conect it can u help me find them

asked by: James H

Expert Reply:

From what I know there are no tow package wires under the dash in the 1998 model year GM trucks. The under dash wire harness started in 2007. And from 1999 to 2006 there was a port under the dash. But for 1998 a brake controller like the # 5504 has to be hardwired in.

If the truck does not have a trailer connector you will need to first add a 4-Way using # 118315 for a deep drop bumper. If it already has a 4-Way or using the one just installed you would then need a 4 and 7 Way installation kit # ETBC7. I have included a link to an FAQ that will help explain this installation.

If the truck has a 7-Way then you will need installation kit # 5506 for 6 to 8 brakes. You will need to connect a wire to the blue brake controller wire and route it back to the back of the 7-Way in the 7:00 position.

For the rest of the wires for the brake controller you can follow the relevant parts of the FAQ article I have linked.

expert reply by: Michael H