Mine has been fairly bulletproof for over 9 years and almost 100k miles. But you have to stay in front of the maintenance. It’s not a “break fix” car, meaning, you don’t want to think you’re going to drive it until it breaks, fix it, then keep going. That’s reactive, and any Benz will break you that way. Stay proactive in your maintenance and like most things on a Benz, if it breaks you’ll only replace it once in your ownership. It also depends on how you drive it, garage kept vs. outside, etc., YMMV.

maw

Same. If you stay in front of the maintenance (oil change every 5k, power steering and brake fluid every 2 years, SMG fluid every 3 years or 30k) and you’ll be fine, as long as you drive it like you have some sense. And even if you drive it like you stole it. It’s certainly not as robust as ANY SClass, to be clear. It’s a 3 series after all. So you may replace things twice in your ownership. But on both cars, you MUST stay away from aftermarket parts. They’re generally allergic to them, which makes sense. They are what they are because of the robust factory parts. You start swapping those with Chinese and Korean this and that, then you may as well have a Kia or a Hyundai, because that’s what you’ll be left with.

One last thing, common to both cars, is the Pentosin hydraulic fluid that drives both the SMG pump and the ABC system. When it first came out 15 years ago, people thought it was a “lifetime / no change interval” fluid. They thought that for transmission fluid too. History has shown that to be nonsense, in both applications. So if you change that Pentosin every 3yrs/30k Miles, you wont have trouble out of the SMG (BMW) or ABC (MB) systems.

GL,

maw

To build on this, I actually think if you stay on top of the fluid and the accumulators, the hoses don’t blow because you won’t have pressure spikes in the system. But his point is absolutely correct in that you have to think of it as a SYSTEM, not as individual components where you only attend to the one component at a time. Do all accumulators at the same time because if your pulsation damper is making noise, chances are they all need changing and you may as well do the fluid at the same time. That sort of thinking keeps trouble at bay with these.

GL

maw