Just passed 80k miles in my 2016 340i. Nothing but routine maintenance. I’ve also got a stage 2 high pressure fuel pump, catless downpipe, and a tune pushing 450+HP to the wheels.

if you know anything about toyotas then the B58 in the Supras should be enough to answer questions about reliability

I’m at about 77k miles and going strong. Radiator and coolant reservoir have been my only reliability issues. Had those both go out around the same time but replaced under warranty. I’ve also had a DRL and my grill shutters go bad, but I coded my DRL to run brighter which probably caused it to burn out, and the shutters are an issue specific to 2018 models and is warrantied for 15 years/150k miles.

There are tonnes of threads on this. B58 is great. Recommend taking a look at Bimmerpost for common issues which are very little with B58 depending on the year you’re looking at buying. Mine is 2017 first gen B58. I’m at 113k kms which is just past 70k miles. Car’s been great. Love it and mine is fully optioned which I do recommend. First gen had expansion tank issue which I took care of and the front air flaps which under warranty for 15 years as it’s been a common issue. Mine appeared on 2021 and BMW took care of it. Other than these two just the maintenance was my cost.

Own one, love it. Currently at 59,000km on my 2019 540i. I’ve had no issues with the powertrain whatsoever. There have been some other issues with the car that were dealt with under warranty:

- emergency telecoms had to be replaced due to water entry near the antenna

- active shutters had to be replaced as they were stuck in the open position (known issue)

- slight coolant loss (known issue with the B58), dealership noticed the oil filter housing was sweating so they replaced it.

Other than that it has been a great car; best I’ve bought. I think the 5 Series has the best build quality of the German brands in the segment, and the B58 and ZF8HP transmission is one of the best powertrains in the industry. Because BMW is putting it into just about everything, parts availability should be there for quite some time.

There are a couple of issues that may need your attention: 1) if the heater core fails and needs to be replaced it will be an expensive fix given it’s location and the labour involved and 2) the running day lights may be prone to failure/burnout and that can be an expensive fix/replacement.

Just stay on top of the maintenance, and remember that the problems won’t necessarily be with the powertrain but everything else around it that can go bad. BMWs have been known in the past to have issues with their cooling systems and electronic gremlins. Not sure if any of that has really gone away, but can say with complete confidence that the build quality and engine reliability has improved a ton in the past 5-6 years.

Only issue on B58s that I am aware of is the pcv diaphragm getting a hole in it. I replaced mine in 5 minutes for like 20 dollars. Aside from that no issues whatsoever

The B58 is one of the best BMW engines and one of the best modern engines. There are far more positive stories than negatives. Some people have their issues, but that doesn’t take away from the thousands that don’t.

I’m just about to hit 60k on my 540i. I’ve had a few repairs done but warranty covered thankfully. This engine is just butter. That’s the only way I can describe it. It purrs most of the time and then growls when pushed. It never feels like it’s really working hard. It just sounds and feels so good. Engine wise, the PCV valve (+gasket, o-ring, valve cover) is really the only issue I’ve had.

I don’t know if or how I’ll move on from this engine when my warranty expires.

Cough…cough…injector failures…cough

2018 b58 here. Zero issues 70k miles. Hammering it every day on my way to work and back.