Several customers of GM vehicles with tow functionality report receiving a “service trailer brake system” error message and audible alarm that is supposed to indicate an issue with the trailer’s brakes. However, customers are experiencing this issue when there is nothing attached to the tow hitch. In addition to substantially compromising users’ driving experience in breach of the implied warranty of merchantability, the alarm presents a safety issue with its potential to distract drivers.

When some users who are experiencing this issue do attach a tow load, they are unable to go faster than ~ 20mph due to the truck’s tow safety mode. Some users report this ‘safety’ mode engaging while they are driving at high speed on the highway, causing drivers to panic as they try to figure out how to get off the road. Some users believe the issue is an electrical one, and maintenance targeted at the vehicle’s electrical system seems to resolve the issue. The issue affects the 2008 Sierra, the 2014 Sierra, the 2015 Sierra, the 2018 Sierra, 2020 Sierra, the 2014 Silverado, the 2015 Silverado, the 2016 Silverado, the 2017 Silverado, 2021 Silverado, as well as likely other vehicles.

GM appears to be repairing vehicles under warranty.

GM does not appear to have any class action waivers or mandatory binding arbitration provisions in its warranties or terms and conditions.

Ford faced a similar class action lawsuit in 2021 over allegations that their vehicles’ towing systems were faulty and dangerous, randomly releasing the load that was being towed.