Hi scotty I am looking to buy a bmw m240i in England with b58 engine. It is the same engine in new Toyota supra so I’m wondering if it is a reliable engine since it is being used by Toyota. Thanks
The way I look at the B58.
BMW engineered.
Toyota tested.
Austrian built. Not Japanese or Toyota built.
So the B58 may be better in terms of reliability versus other BMW engines. But not as reliable as a bonafide Toyota engineer, tested, and built product.
Mind you, there is no evidence to back this claim directly. Only the history of other products developed by these companies.
The B58 is 5-6 years old now and has shown very good reliability thus far. A couple of things to keep in mind are that a performance engine (or car for that matter) will never be as reliable as something like a commuter car. Also keep in mind that 5-6 years starts being considered old for any BMW.
As a BMW owner, in general I would say that the B58 (or drivetrain in general) is not likely to be the weak point on an M240, but do not expect it to be a car that you can drive much beyond 100-150K miles/160-240 Kilometers.
Toyota uses many other companies' products but that does not mean that they are always reliable. For example, yamaha engines rebadged Mazdas and Subarus etc.
The B58 is a wonderful, fuel-efficient, robust and smooth engine and thanks to its closed-deck design which makes it stronger and having the ability to handle more power, it's way better than previous BMW inline 6 engines like the N54 and N55 (N54 was probably the worst inline 6 engine that BMW produced since that was when they attempted to turbocharger a six-cylinder which were disastrous). There is also the S58 that is based on the B58 but has an extra turbocharger and used in the X3M, X4M, M3, and M4, a very strong engine and so far haven't heard any issues. It's one of those engines I would actually go for if I were to buy a BMW and they know what they are doing with their 6 cylinder engines since they have been making them for decades and having it in a Supra and 2 series make for an enjoyable experience.
No one knows yet.
I am looking into the exact same car, and if you are going to buy a BMW that is the car you should get, it is the most reliable car in their line up. It has the least tech because it has the previous gen interior and features, it has the B58 like the Supra, and also has the zf8 hp auto transmission or a 6 speed manual. It will not be as reliable a Toyota, but they haven't had issues yet, and the B58 is almost 6 years old so you may not have too many issues.
