May I use conventional oil for an oil change in my 2013 ford focus?

Best way to figure this question out is call your local Ford dealer and ask most of the time the warranty requires certain shops but other times it doesn't. It just depends on your Warranty.

I have to agree with this one - your owner's manual will also state which types (weight and API service Rating) to use. Personally, I believe that Synthetic oils only offer longer intervals between changes but otherwise have few additional benefits. Manufacturers love to change up service intervals to boost the brag of fewer maintenance needs but never mention the extra costs. Marketing $#@!

Use the recommended oil and read about motor oil on this site - http://www.bobistheoilguy.com/motor-oil-101/

I think you're problem may be with being over charged. I take all 3 of my Ford vehicles to the Ford Dealership and am charged $29.95 for the semi-synthetic 5w20 and sometimes its on special at $24.95. This service includes checking all the other stuff that needs checking (tire tread, pressure, battery charge etc. I can't imagine why you would be charged much more than I am (maybe up to $39.95) and on the other side of the coin I can't imaging you being charged much less for "conventional" oil unless it is used oil or unless they low ball you in with oil change price only to force you to get your tires rotated, and charge you to top off the windshield washer fluid. You would be ill served to skimp on the proper oil and you would be well served if you opt for full synthetic. If you go with the "conventional" oil, a penny saved will not be a penny earned. take care,.........ldc