I am not a mechanic, but I do the simple stuff to save money and the hassle of having to leave a vehicle at the shop and pick up later. RockAuto is very helpful on finding parts and they process your order quickly. paying for shipping is like burning gas going to the store, only to find out your item is out of stock, so you can burn more gas going to another store. with RockAuto you know if your parts are in stock before you order, which keeps me from wasting time driving to town and jumping from store to store. About the only thing I buy at the store anymore is oil and oil filters. After my first purchase I started dancing like the animated guy on the tv commercial.