From what I can gather if you have a 3.1 L engine it may have something to with when engine shifts, if you go to the parts dept. at a GM dealership the counter guys will usually be able to show you a diagram of where the part is located. I'm guessing on the outside of the trans axle.I don't know what symptoms your car is having to make you check it. Haynes is not as thorough as a shop manual. Good luck.