Engine oil OEM Mazda or OEM BMW

3.0 n52 when I got the car it had 5w-30 and the oil was leaking slightly. Changed 5w-40 and the leak stopped all together. Engine is smooth as butter

I prefer synthetic myself in my CX50 Turbo, but Mazda engines aren't very picky overall.

5W-40 is my preferred viscosity for the N52. If you are only topping off, virtually any API SL or newer oil will work just fine. If you are doing a full change though you should source a 5W-40 that meets BMW’s LL-01 specification.

As long as it’s a LL-01, you can put that in. I’m currently running that on my N52.

10w60 is the only oil you should put in these. If nothing else, you can usually find it at BMW automobile dealerships as that is what they put in the M3/4 series (or at least used to). Not cheap, but a lot less expensive than engine rebuilds.

Change the oil at a minimum, and do it regularly. Use a quality synthetic high mileage oil and change it again in a couple thousand miles, then change on regular 5k mile intervals.

A lot of people are essentially saying "don't beat on it until that gauge reads warm," which is incorrect. BMW, in the G series, switched to showing *coolant* temperature on the speedo and not oil temperature. That is NOT the oil temperature gauge, and oil takes a lot longer to heat up than coolant. When that gauge shows operating temperature, give the car another 10 minutes or so to get the *oil* up to temp.

Nah you're fine. BMW engines are known for using some oil. Even 1l on 5k km is not much, even the dealership considers this as normal.

Lots of BMW's as they get in to the upper mileage tend to start consuming oil one way or another.

10k miles later, went to do my usual 1k mile quart of oil, looks like chocolate milk.