In my first report on the newly acquired M3, I mentioned that the rod bearings are a known issue on the S65 4.0-litre V8. To recap, because of the engine's characteristics (like that 8,400rpm redline), it needs some pretty special 10W-60 oil. For a frame of reference, that's same oil that you'd find in the in the sump of a Bugatti Veyron.
The downside of this oil (aside from it being expensive) is that when cold it is very thick. This, combined with extremely tight tolerances on the rod bearings of the motor, mean that if you rev the car hard from cold, you can do some serious damage. What's worse, this doesn't happen immediately. Instead the problem manifests itself much later, the V8 working absolutely perfectly right up until it doesn't, and you find yourself stranded as traffic runs over the oily remains of your recently liberated engine internals.
Aside from asking the previous owner if they diligently warmed the car up before making use of that mighty rev limit (which I did), the only way to tell if the bearings might be worn is with an oil sample analysis, although the results of these should also be taken with a pinch of salt. Nonetheless, as mentioned last month I sent away a sample to Millers Oil's lab, the princely sum of £29 seemingly worth it for the peace of mind I'd get from knowing my car wasn't showing any symptoms of rod bearing failure. Or was.
In short, the oil analysis showed very high levels of copper and lead in the oil. Copper is what bearings are made of, once the lead outer shell has been worn away at least, the wear more often than not caused by - no prizes for guessing - using 8,000 revs from cold. Brilliant.
If you scour the internet for discussions on this subject (and believe me, I have) there are extremely mixed views. On the one hand, the actual number of failures are fairly low so people think you should just get on and enjoy the car and not worry about it. On the other, there is a school of thought that says that for £1,400 you can have the bearings replaced and - as long as you let the car warm up - you'll never have to worry about the motor again, which is very reliable aside from this issue.
For me personally, I just couldn't live with the fear of the engine letting go; it was stressing me out and spoiling ownership of the car. I immediately did some research and got the car booked in at well-known BMW maestros Evolve Automotive for the bearings to be replaced, and whilst I waited for the appointment I introduced a temporary 4,500rpm rev limit, such was my paranoia of catastrophic engine failure.
Evolve have replaced hundreds of sets of rod bearings in E90 M3s (and E60 M5s, which suffer the same issue - not surprising given that the engines are very closely related). They also have a reputation for building some absolutely wild McLaren 720S-beating-M5s, so to say they're qualified for the job is somewhat of an understatement. After dropping the car in to them and having a good look around their huge fleet of aforementioned bonkers demonstrator cars, I returned home with bated breath to find out just how accurate that oil sample had been.
Evolve carried out the work quickly and efficiently, keeping me up to date with how they were progressing as they stripped the engine down and replaced the rod bearings and engine mounts, which are always replaced at the same time as they are nearly as inaccessible as the bearings themselves.
Now, in my experience, when someone tells you that something is "not the worst they've ever seen", it usually means that it is, in fact, the worst that they've seen - they're just being polite. And, as you'll see from the pictures, the bearings that came out of the car were, and forgive me for getting technical, more rogered than a policeman's radio. There is obviously no way to tell how long they'd have lasted, but I can tell you with absolutely confidence that my drive home from Evolve (and every drive in the car since) has been absolutely brilliant. Where previously there was stress, now there is only joy, the mix of acceleration and noise at 8,400rpm is something that I can't see myself getting tired of. Right now, it feels like money very well spent.
With the car now mechanically fit and healthy (aside from soon needing some new rear brakes), time spent with the M3 has been fantastic. So fantastic, in fact, that I felt like the car deserved some pampering to make it look as good as it drives. I personally really enjoy cleaning cars, but with a young family and a busy life, I never seem to have time to do it 'properly'. Professional help was needed.
Smart Mobile car detailing are a young business who are completely mobile and offer both one-off detailing, or a regular subscription service to keep customer's cars looking their best. I was a little worried before they were due to arrive as the car was absolutely filthy, but owner and operator, Nick, is clearly one of those people that take great pleasure from getting really dirty cars really, really clean. And I'm not judging him for that!
Starting with the obligatory snow foam, Nick got to work the usual process of cleaning every nook and cranny, then using a clay bar, followed by about a million tiny steps and finishing with a polish - the end result looked incredible. Perhaps more surprising was how well the interior came up; after deep cleaning the leather and hoovering the interior to within an inch of its life, the cabin genuinely looked like new. Things like this are so hard to show on camera, but I can't believe that the car looked much better when it rolled out of the dealership for the first time back in 2008.
In the end Nick spent over six hours on the car, which for £200 seems like incredible value, especially given how much better a job he has done than I ever could have, and the fact it would have taken me five times longer. Perhaps better still is the 'top up wash' they offer for just £30. This is a proper, professional wash for the same price as a petrol station 'manned car wash', just without the gravel-laden sponges and from the comfort of your own home or place of work.
As the car sits on my driveway now it looks superb, and it is now well and truly ready for some road trips I am planning over the coming weeks. Every time I have an excuse to spend time in the car I jump at it, and to me that is truly the sign of a driver's car. More on that next time.
Car: 2008 BMW M3 (E90)
Run by: James Drake
Bought: February 2019
Mileage at purchase: 35,555
Mileage now: 37,693
Last month at a glance: With the engine in rude health and the paint back to its best, James prepares for a summer of M3 loving
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