Synthetic car oil. Just bought an Audi A5 4.2L Quattro. My mechanic recommends synthetic. Car has 128,000 penn highway miles. Is it worth it? Does it help? Thanks


Asked by Aug 29, 2012 at 10:01 PM about the 2004 Audi A6 4.2 quattro Sedan AWD

Question type: Maintenance & Repair

4 Answers


I've been told that you can switch FROM regular oil TO synthetic oil. BUT you CAN'T switch back or FROM synthetic oil TO regular oil because your engine will leak like a seive. Be careful!! -Jim


You can make the switch to synthetic no problem. You won't notice a difference while driving but you will over the life of your engine. It burns cleaner and has less resistance than conventional oil so you'll see less wear and tear over time. The only thing that sucks about the 4.2L V8 is how much oil it takes. You're looking at almost 8 quarts and synthetic isn't cheap. If you have the cash to spare, make the switch, it'll be better in the long run. If money is tight, you'll get along just fine with the conventional.

Best Answer Mark helpful

Thanks for the info guys...


You need to use the manufacturers recommended oil or better to assure good functioning of the engine. Also the difference of synthetic oil is that is man made 100% not mineral so it is cleaner and gives more mileage but do not exceed the maximum mileage for oil change the car's manufacturer specifies to avoid engine damage. The use of full synthetic in some cars is that they permit long periods for oil change and you can get advantage of that. Hope this adds some help

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