Engine oil OEM Honda 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

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.

I put used vegetable oil in my Honda Accord 7k intervals has 380,000 miles on it

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.

Just drive it. With these 0w20 oil is circulated immediately. My G20 330e does a cold start when accelerating the highway. The RPM limit is protecting your engine so even with a kickdown it won't go above 4k RPM and will shift very early.

I ran 10W-50 and 10W-60 for a few years in an old and beaten up Honda in the hope of reduce oil consumption to avoid having to open the engine. Long story short: it's not harmful, it's an expensive gimmick, the only real-life effect is fuel consumption will slightly worsen and that Honda had occasional issues with VTEC (a well known issue in those engines when running high viscosity oils).

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.

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