which oil you would recommend?

[Rockiii]

Hey guys, i know i will start a heavy discussion now, but which kind of oil you're using? 

I'm living im germany, most of the bmw engines are running with 10W40 oder 5W30 here, but which are you running in which location?

[DesktopDave]

I run pretty thick oils to preserve the motor, but I've lost about 5% in fuel mileage due that choice. My favorite here in the Northern US is "synthetic" Mobil1 15w50, largely based on cost and availability. I run it year-round. My used oil tests (from Blackstone Labs) have determined that thinner oils (like 0w20 and 5w30) allow very high wear in my very high-mileage motor. Mine is approaching a half-million KM (290K miles) and she's seen better days.

Your European oils aren't the same as ours - they're labeled differently due to America's sloppy standards. Mobil1 (Group III) is labeled as 'synthetic' here but must be sold as 'conventional' motor oil in Europe. All major manufacturers offer high-quality synthetic oils. I'd suggest Castrol, Motul or Liqui-Moly synthetics; I've had good luck with all of them, and they're very high quality.

For more lubricant information than you could possibly need:
http://www.bobistheoilguy.com/forums/ubbthreads.php

[deansweet]

Not wanting this to become an infamous 'oil thread' but I run Castrol1 5w30 Extended Performance Synthetic(15k mile one) in both my E30's and the results speak for themselves.
This is the head of the 318i with 181k:

[Rockiii]

Not wanting this to become an infamous 'oil thread' but I run Castrol1 5w30 Extended Performance Synthetic(15k mile one) in both my E30's and the results speak for themselves.
This is the head of the 318i with 181k:

This looks very good to me, what about the oil consumption with this oil?

[Nick_318is]

I use Shell Rotella T 15W40

[deansweet]

On the 318i, it uses/loses about .5qt of oil per change. I change the oil every 6months which is ~3500 miles since he lives, works and goes to school in downtown Cincinnati.

[keflaman]

I use the oil I drain out of my "good" cars which is Mobil1 sumpin-30W. I don't particularly care about this engine and if it blows I'll finally have the motivation I need to build the motor I took out of it.

[romeomike]

I'm stabilizing on Mobil 1 15W-50, having tried their 10W-40 high mileage, and 0W-40 European formulas.

[DesktopDave]

I use the oil I drain out of my "good" cars which is Mobil1 sumpin-30W. I don't particularly care about this engine and if it blows I'll finally have the motivation I need to build the motor I took out of it.

I do the same thing, but the BMW is one of my 'good' cars, LOL. I've found that the cars "break-in" the synthetic lubes a good bit, and that's perfect for my motorcycles. Wet clutches tend to slip with low-friction synthetics ("Energy Conserving" types), but used synthetics work very well. I've been doing this for years, getting 'free' oil for my bikes. Some of the lubes I use are fairly expensive, but they'll likely go through three vehicles before recycling!

[Jay]

This may be an old folder but it does give some insight into different types of oil

http://www.hardemanmotorsport.nl/vergelijkend_onderzoek.pdf
 

[Tgoode318]

Thanks for posting that link jay it was very interesting. Looks like im in good hands with Royal Purple  . I know this sounds cheesy but i became a royal purple customer after trying there in store test. The test has two different gears that you can crank by hand, One gear is in royal purple and the other is in some random low budget oil.  When you turn the low budget oil there is allot of resistance and you have to put a little force to turn it. Go to the gear with royal purple and the gear almost turns itself! A night and day difference between the two. Not knowing if it was marking hype or not i went ahead and did a full oil change with RP and havent looked back since. Its good to see some actual numbers proving what they say is true unlike some of the other high dollar oils mentioned in the link. I would Recomend RP to any one looking for a good oil.

[Jay]

I think Royal purple is a bit expensive plus I have to drive very far to get it. So al my cars run on Valvoline Durablend.

[DesktopDave]

RP is good stuff, I run it in my '84 745i. Red Line is another good company, as is Amsoil. While I have my reservations about Amsoil's "Mary Kay" pyramid marketing, but they do seem to make good products. IMHO they're all overpriced, but they have excellent quality. Those gear tests are just marketing hype, check out BITOG for really in-depth details about lubes.

AFAIC, the best "bang for the buck" are the synth blends, or the cheap 'synthetic' Group III lubes like Mobil1. You can safely extend oil change intervals over 10K miles, and get most of the benefits of pricey PAO lubes.

BTW - heard that NAPA offers pretty cheap used oil analysis at their stores. They're likely reselling a Wix service (Wix 24077 Oil Analysis Kit), those might be even cheaper. Regardless, $14+shipping to know what's going on in your motor is hard to beat.

[benz-tech]

I use Mobil1 5w40 because I feel it works well even with flat-tappet cams, both on this engine and the Nissan V6 that was in my 510 (w/ 280deg .480" re-ground cams. It shouldn't, I know. It has also cleaned the insides of my 230k mile M42 that was nowhere near as clean when I bought it. For me its free so that helps bias me towards it. but if it didn't work I wouldn't use it at all. + Mercedes and AMG approves it so...

[selespeed]

has anyone tried the German Castrol 0W30? i am tempted to try this as it is said to be very good. i have tried mobil1 0w40 and now on castrol 5w40. while the mobil1 is quite good, castrol is noticebly better.

since last may 2014 i had the engine rebuilt with new con rods, bearings, pistons and valves and been on mobil1 0w40 and 39,000km later i want to go back to castrol.

some say our engine m42 is too old to use 0w30 thin oil. any truths in this?

teo