recently i notice my 2015 suburban ltz after putting some luggage in the rear that it wen up. i saw suspension going up about an inch. now that happened before how ever then it goes back down.. but this stime it stay up and never came back down and now it rides real stiff. unfortunatelly its now with 80k miles so no warranty . extremely dissapointed with gm products.. this vehicle water pump wen out at 46k miles. the gps antenna is no longer working so i cant use navigation. also have a cadillac xts and nothing but problems with that vehicle. i regred going to gm product. any help will be greatly appreciate it.