Switching back to 10W40 from 5W40 - M52

[MisterM52]

Hello Fellas, Been a while, I have been using 5W40 Shell Helix Ultra on my M52B28 for over a year now, Car only sees maybe 2000-5000 Miles a year, I was previously was using usual 10W40 with no leaks maybe a drop in months, engine noise went up, slight more burn I feel like it, Doesn't really snow here where I am at, winter is nothing special. So overall costs and all concerned I am Switching to Castrol MAGNATEC 10W-40.

My Verdict: Helix 5W40 is Great Stuff, if it was a rebuilt engine from ground up, I would go with it. However on a 20 year old engine thats not had all gaskets replaced, in the future, I probably wont go with it or fully synthetic, better off with good grade the semi synthetic stuff as the Magnatec or regular imho, cheaper so more frequent changes or topping up if need be, less hassle, leaks overall, I like how my engine behaves with that stuff too, So I am sticking to it.

[Eric93se]

Whatever weight you choose it should be full syn, you can leave it in there for a few years if you don't drive it much.

[JEC928]

No review of motor oil is complete without hard data - send a sample off to a lab for analysis. Metal content and how much molecular breakdown will be the results.

Other data points would include engine (not chassis) dyno tests with your oil and other oils as an approximation of friction losses.

Human senses cannot detect good oil vs bad oil.

[MisterM52]

Well a week into use, I am so far loving it far more than the 5w40 helix ultra. just is more responsive, smooth delivery and holds power better, less or no noise part my fan and the belt. win win so far I'd say.

[B320i]

Different engines react different to different oils. Not surprising to note a difference in engine sound after a fresh oil change, particularly if you've moved to a different grade and/or formulation.
I say, if it meets the ACEA A3/B3 (or B4) spec., is the right grade for our engines (xW-40 or higher, mostly) and can be found at the right price, go for it.

Particularly for earlier E36s with the M50, mineral, semi-syn or full-syn oil doesn't matter much, particularly with a shorter factory oil change interval compared to later M52s. Outside of the U.S.A., one can source even minerals oils in the 15w40 grade that meet the latest API specifications, in addition to the crucial A3/B3-B4 spec. The Owner's Manual of these cars called for BMW Special Oils; which at the time were oils that met CCMC-G5, a precursor to the ACEA spec. cited above.

In Australia & NZ, fully-syn oils can run 2-3x the price of conventional, or even semi-syn grades. Conventional & semi-syn oils are also most likely to be on sale for dirt-cheap prices. So in the end, fully-syn just doesn't work out if you're running shorter oil change intervals.

[MisterM52]

Different engines react different to different oils. Not surprising to note a difference in engine sound after a fresh oil change, particularly if you've moved to a different grade and/or formulation.
I say, if it meets the ACEA A3/B3 (or B4) spec., is the right grade for our engines (xW-40 or higher, mostly) and can be found at the right price, go for it.

Particularly for earlier E36s with the M50, mineral, semi-syn or full-syn oil doesn't matter much, particularly with a shorter factory oil change interval compared to later M52s. Outside of the U.S.A., one can source even minerals oils in the 15w40 grade that meet the latest API specifications, in addition to the crucial A3/B3-B4 spec. The Owner's Manual of these cars called for BMW Special Oils; which at the time were oils that met CCMC-G5, a precursor to the ACEA spec. cited above.

In Australia & NZ, fully-syn oils can run 2-3x the price of conventional, or even semi-syn grades. Conventional & semi-syn oils are also most likely to be on sale for dirt-cheap prices. So in the end, fully-syn just doesn't work out if you're running shorter oil change intervals.


Hey Bud, Long time. Yea totally, the last part in particular, I got 8L of Magnatec (2x 4L) for about $60 on Sale from the SCA with Club Plus Card while it went on easter sale, while the Hellix Ultra stuff was still way over $80 for 4L. So for around that price I was able to even grab a filter. Just to try it out since I have used that oil in another car and it went smooth. Very happy with this one so far, 10W40 that meet the specs is what I always used, then switched to 5W40 but that just felt weak, unnatural, now back to 10W40 but magnatec (semi synthetic) and so far so good.