Use exactly what Audi recommends as listed in your owners manual and nothing else. Your A4 requires an oil that meets the VW 502 specification. Nearly all oils that meet that spec are a 5w40 or a 0w40 synthetic product, Mobil One 0w40, Amsoil 5w40 European formula, Castrol 0w40 European formula, the best performing being the Amsoil with the Mobil One very close and Castrol is adequate. Read the back of the bottle and ensure it states that it meets the VW 502 spec/ACEA A3/B4.
Do not use a 10w30 in that engine if you want longevity for you or the next owner.
10w30
motor oil 10w30
10W30 5 quartz
The manual calls for a 10w30 motor oil. Just any 10w30 motor oil will work depending on your preference of brand.
10w30
10w3010w30
For a 3.2L engine use a good quality 10W30 motor oil.
5w30 or 10w30
Not recommended. Use 10w30.
SAE 10w30 any major brand.
SAE 10w30 any premium brand.
10w3010w30