Firestone Complete Auto Care also offers a Code Scan for Free when you present this Printable Coupon. Coupon is valid through 7/31/15.
Editor's Notes & Price Research
Valid for most vehicles and in most states. Certain exclusions may apply. An additional fee of up to $2.50 may be added for oil filter recycling.
Refer to the forum thread for additional information.
Install New Oil Filter
Refill up to 5 qts with Kendall GT-1 Motor Oil
There is also a coupon for a free code scan. Basically, if your engine light is on they'll read the code and tell you what is wrong. On a side note, auto zone will do this for you for free anytime (UPDATE: Not in CA). But hey, if you need an oil change and your engine light is on, they won't charge you... this time.
How many miles does your manufacturer recommend in between oil changes? Check out that link, you may be surprised. Note: This works only for vehicles manufactured 2000-2014.