Video - Do S55’s have a Rod Bearing problem?

[Matt@Evolve]

We all know that BMW's M engines are no stranger to wearing their Rod Bearings a little more than we'd all like. It's been a hot topic especially for S65/S85 owners, but we haven't heard so much about it on the S55 found in the M2C/M3/M4 - Does this mean BMW have fixed the problem?

Well there's only one way to find out, during the Crank Hub upgrade on my M4 we dived a little deeper and pulled the standard Rod Bearings out to see just how worn they are after 130,000 miles. We then upgrade them with Mahle Motorsport Bearings.

What do you guys think? Would you bother doing the Rod Bearings on their own, or consider it when doing a Crank Hub?

[M_Torx]

honestly who knows how the last person or owners drove the car if it was tracked or drifted a lot sitting at redline rod bearings are going to be worn compared to a car that was babied also if one plans to keep the car for a long time and drive it hard track or drift would be a good idea to do RB... would suck buying a new motor lol ...so many variables might as well just do RB if car is over 100k especially if your doing CH

[NickyC]

Not this shit again.

The answer is NO.

[Drifter2090]

Wow bearings looked great on that car!
Probably safe to say s55 doesn't have bearing issues (unless you never do oil changes!), don't think I've seen anyone post excessively worn bearings yet.

[M_Torx]

Originally Posted by Drifter2090

Wow bearings looked great on that car!
Probably safe to say s55 doesn't have bearing issues (unless you never do oil changes!), don't think I've seen anyone post excessively worn bearings yet.

all depends like you said lots of oil changes but how hard you drive definitely plays a part this car was probably on the ring alot 🤔

https://www.bimmerpost.com/forums/sh...php?p=26791454

[Drifter2090]

Originally Posted by M_Torx

all depends like you said lots of oil changes but how hard you drive definitely plays a part this car was probably on the ring alot 🤔

https://www.bimmerpost.com/forums/sh...php?p=26791454

Yeah and also getting the oil up to temp before revving high plays a big part in wear

[Matt@Evolve]

Originally Posted by Drifter2090

Wow bearings looked great on that car!
Probably safe to say s55 doesn't have bearing issues (unless you never do oil changes!), don't think I've seen anyone post excessively worn bearings yet.

That's pretty much our findings - It may be worth doing if you're also doing crank hub as a 'while you're in there' but I certainly wouldn't be losing sleep over a set of original bearings even at a fairly high mileage like mine.