NEVER GO TO A WALMART FOR AN OIL CHANGE! My local Walmart destories cars...
The mechanics that work there are the mechanics left over from the good ones because they actually work in garages.
Example:
Mechanic(if you want to label them that) only added 2 quarts of oil into a car. Walked away to go get more. Another Mechanic thought it was done and gave it to the person with only 2 quarts of oil and destoryed the motor!