The problem led to 113 accidents and 13 injuries, although no casualties were reported, GM spokesman Dan Flores told CNN.
"General Motors Voluntarily Recalls Some 2014-2018 Cadillac Escalade, Chevrolet Silverado, Chevrolet Suburban, Chevrolet Tahoe, GMC Sierra and GMC Yukon for a condition related to increased brake pedal efforts, "GM said in a statement. "In rare circumstances, these vehicles may have a condition in which a mechanical vacuum pump can be reduced over time by reducing the amount of vacuum / braking assistance required."
Because the pumps in the brake are boosted beyond less vacuum power than necessary, "customers may experience increased brake pedal, hard brake pedal, and / or potentially increased brake path."
All these problems can increase the risk of a crash.
Flores says the problem is more widespread at low speeds when the brakes are applied softly and that the brakes continue to function and exceed the requirements of the Federal Motor Vehicle Safety Standard.  While the National Highway Traffic Safety Administration (NHTSA) began investigating the issue in November, GM has only been in contact with NHTSA for several months on the issue.
NHTSA did not respond to a request for comment via email, and
GM was asked to act on the basis of field reports and customer complaints.
'Dealers will reprogram the electronic brake control module in these vehicles with a new calibration that will improve the way the system uses hydraulic brake assist.
Dealers will calibrate the electronic brake control module free of charge for customers.