Special Coverage Adjustment - In some circumstances, some 2014-2018 model year Cadillac Escalade, Chevrolet Silverado, Chevrolet Suburban, Chevrolet Tahoe, GMC Sierra, and GMC Yukon vehicles may have a condition where customers may experience increased brake pedal effort, hard brake pedal, and/or potentially increased stopping distance. The condition is more prevalent at low speed when softly applying the brakes. The engine mounted mechanical vacuum pump output may decrease over time decreasing the amount of vacuum/power brake assist. Failure to follow recommended oil change intervals could contribute to this condition. The Driver?s Information Center, (DIC) ?Service brake assist? alert will activate 2-5 minutes after the vacuum level drops, and a Diagnostic Trouble Code, (DTC) will also be set. Even where this condition occurs, the hydraulic brake system remains functional but may require additional pedal force. Dealers are to replace the vacuum pump and vacuum pump belt. The repairs will be made at no charge to the customer.
