Oil service opinion

[Chillipepper]

Is using castrol edge 5w30 overkill on my e36 323i touring.

Picking up my service items yesterday brake pads, oil and filter, the chap in the motor factors seems so. Oil changed every 5-8k miles. I have never had an ounce of trouble from the car in 2 years of ownership and want to keep it that way.

[Peter-E36]

How many miles are on it? if it's 100k+ I'd say use 10w40. You can use 5w30 anyway (that's what BMW recommended when it was new) but keep a very close eye on the oil, I found my 323i burned a bit of oil on 5w30 so switched to 10w40 and it didn't burn anymore after that.

[Smokey Bear]

Castrol is shit and 5w30 is probably too thin.

[Chillipepper]

Hi peter just ticked over 150 k

[dergside]

I'm a firm believer in frequent oil changes, especially as cars creep up in age and miles, and in not second guessing the engineers that spec'd the oil grade in the first place. My engineering expertize probably wouldn't stand up to the same level of scrutiny theirs would.

The only reasons I would change grade is if you're not inclined to keep a fairly regular eye on oil level (Chilli, I'm guessing you are on top of things like that ) or if it was burning oil at a significant rate. The main reason an M52 that has been well looked after might burn oil is some level of nikasil related degradation in compression. Any M52 cars I've had have been as tight as a duck's ass when it comes to using oil.

If its burning oil to the extent that it needs a top up more than once between full changes then think about changing the grade. Otherwise, if it ain't broke.....

The only car I've changed the grade on is a 330Ci I had years ago. The M54's can sometimes burn a little bit and this one was using enough to need more than a litre between changes.

[Chillipepper]

I was thinking the same myself Dergside, it has not done any harm to date with the mileage now in the 150 k range, now more than ever I want to make sure the oil I am using is up to the job.

[Peter-E36]

I'm certainly no mechanic, but what was explained to me was that with age and mileage the 5w30 that was recommended when new will seep through the (piston seals?) and get burned, so switching to the thicker 10w40 oil prevents that to a large extent.

The nikasil issues were nearly 20 years ago, so any engine's either been fixed or replaced, I wouldn't be concerned about it in 2016 to be honest.

I too am a firm believer of frequent oil changes and changed mine every 5-6k no matter the age of the car I had, if you've no trouble with 5w30 between services then stick with it, if not maybe get a 2nd opinion from the likes of Motor Confidence or Super4 re:10w40 and I'm sure you'll have a reliable answer