NHTSA Complaint #11686951 — 2018 CHEVROLET SUBURBAN

No official incident has happened yet, but the brake assist kicks in, yet does not work until it's revving engine to over 4000rpm, which causes a sudden jerk and scary sounds from engine. I have had a few instances where the vehicle did not want to stop almost causing an accident, and these have happened without anything in the car other than my daughter who is 2 and myself. The most recent problem is a weird rattling sound while going uphill. Before this going uphill is extremely sluggish, where I have the gas peddle almost to the floor, but nothing happens other than decrease in speed until it finally, about 30 seconds-1 minute, where it kicks into overdrive. Even then, speed does not increase by more than 5-10 mph depending on the incline. I have not brought it to get looked at yet, as I've seen these issues have been reported by numerous consumers without any recalls being sent out other than the breaking system update.