First-Generation (2006-2017) The first-generation GMC Acadia was in fact the first unibody-type design from GMC. Moreover, it also became the first front-wheel-drive vehicle from GMC, although it does have an all-wheel-drive option. It has seating for up to 8 people and sits in between the smaller GMC Terrain, and the large Yukon.The first-gen Acadia is related to quite a few other GM-branded. There are many things that can cause the StabiliTrak system to lose its ability to function. It is a complex system. Wheel Speed Sensor – If one of the wheel speed sensors is out, your Sierra will no longer be able to tell if all of the wheels are turning at the same speed. Without this data it’ll turn on the service StabiliTrak warning.