— A GM vacuum pump recall has been expanded by more than 17,500 vehicles after the automaker determined these vehicles, equipped with 5.3L or 6.2L V8 engines, should have been included in a 2019 brake vacuum pump recall.
- 2018 Cadillac Escalade
- 2018 Chevrolet Silverado 1500
- 2018 Chevrolet Tahoe
- 2018 GMC Sierra 1500
- 2018 GMC Yukon
The National Highway Traffic Safety Administration opened an investigation in 2018 into GM vacuum pump failures after discovering brake vacuum pump failures caused or contributed to 110 crashes and 13 injuries.
The pump failures are caused by oil sludge that builds up on the pump filter screen and blocks the flow of oil into the vacuum pumps, reducing the pressure of the vacuum. The automaker says failing to change the oil as recommended can contribute to the problem by allowing debris to turn into sludge.
The condition is more prevalent at low speed when softly applying the brakes, and GM says the stopping distance may increase but the brakes remain functional.
A driver may feel a vibration in the brake pedal or a change in the hardness of the pedal and the amount of pressure required to stop the vehicle. GM also says occupants may hear a ticking noise from the engine compartment, and a driver may notice activation of the secondary hydraulic brake assist system.
In addition, a “Service Brake Assist” message will appear within two to five minutes of vacuum levels less than 10 kPA.
The vacuum pump recall expansion is needed because the previous recall identified a breakpoint in production that was incorrect. The vehicles were manufactured after the prior breakpoint but used the same brake vacuum pumps.
The GM vacuum pump recall is scheduled to begin November 16, 2020. GM dealers will reprogram the electronic brake control modules with a new calibration that will improve how the system uses the hydraulic brake boost assist function when vacuum assist is gone.
Owners may contact General Motors at 866-522-9559, Cadillac at 800-458-8006 or Chevrolet at 800-630-2438.
GM's number for this vacuum pump recall is N202300860.
CarComplaints.com has complaints filed by drivers of the GM vehicles.