If you’re towing a trailer with electric brakes on your 2007–2013 GMT900 Silverado or Sierra, a quality brake controller is essential for safe stopping. Here’s a guide to the best options.
Do You Need a Brake Controller?
Yes – if your trailer has electric brakes (typically any trailer over 6,000 lbs), you legally and practically need a brake controller installed in your truck. Without one, the trailer brakes do nothing.
Types of Brake Controllers:
1. Proportional (Inertia-Sensing) Controllers
These measure the deceleration of the tow vehicle and apply trailer brakes proportionally. Best option for smooth, consistent braking.
2. Time-Delayed Controllers
Budget option – applies brakes based on a preset delay and gain setting. Less smooth than proportional but works fine for occasional towing.
Best Proportional Controller:
Proportional Trailer Brake Controller – Compatible with Silverado, Sierra – Easy installation, digital display, adjustable gain settings.
Installation on GMT900:
The GMT900 has a factory 7-pin trailer connector with a brake output wire. Brake controllers tap into the following wires:
- Red: 12V constant power (from battery)
- White: Ground
- Blue: Output to trailer brakes (7-pin pin 3)
- Black: Brake pedal input (switched 12V when brake is applied)
Most aftermarket controllers include a wiring harness that plugs into the fuse box area under the dash for a clean install.
Setting Gain:
Start with gain at the midpoint. On a flat road at 25 mph, make a moderate brake application. The trailer should brake slightly ahead of the truck. Adjust up if trailer pushes, down if it locks up.
Optional: GM OEM Brake Controller
If your truck didn’t come with a factory controller (optional equipment), you can add the GM OEM controller that integrates with the DIC (Driver Information Center) for a cleaner look.
What brake controller are you running? Any tips for getting the gain right?