Forum Discussion

Paroled's avatar
Paroled
Explorer
Dec 10, 2021

New GMC 2500 Wont Engage Trailer Brakes

I have a new 2021 GMC 2500, Diesel. It will not engage trailer brakes unless the brake pedal is mashed to the floor. It is this way on any trailer it’s hooked up to. My 04 Silverado works fine on my trailer. Dealership could not diagnose. Opened case with GMC and they have sent engineers twice and no luck. Anyone hooked up an aftermarket brake controller to a new GM This has been going on for 7 months
Tow Vehicles
  • ktmrfs's avatar
    ktmrfs
    Explorer II
    Dec 10, 2021
    does the manual control activate the brakes? What is the setting on the brake controller?

    On my 2015 Denali I have it set on 5 and activated brakes on both trailers, and I feel the trailer brakes when I check using the manual control slider.

About Travel Trailer Group

44,029 PostsLatest Activity: Jan 28, 2025