I did oil changes on my E90 myself. I used LM 5w-40. So, I am planning on changing the oil on the G30 every 6 months of 5k miles.
I know BMW recommends LL-14 FE+ rated oil for better fuel economy on the newer BMWs. Can I run LM 5w-40 in the G30 or would that be too thick? I'm not going to be tracking it. Just driving to and from work.
Since you aren't racing, towing or anything like that I don't think going that thick
does make any sense at all. If at all and since it's a turbo DI and fuel is very much
Euro-like low sulphur today I'd go LL-04 and 5W-30 (ACEA C3). There are great oils
out there meeting LL-04. Thicker than that is just robbing power and fuel efficiency.
Would running LL-01 void the 2 years of warranty I've got left?
As already mentioned see your manual.
0w-20 seems to thin to be running in a BMW IMO
Why does it 'seem'/appear to thin to you?
A high power density turbo engine needs a stouter oil.
Interesting theory.
I am sure in Germany they spec a 5w-40, or 0w-40 as they do for all performance
oriented cars there
How 'sure' are you? Your assumption is plein wrong. Actually BMW specs LL-01,
LL-01 FE, LL-04, LL-12 FE, LL-14 FE+ and LL-17 FE+ (which is recommended) in the
EU including Germany plus UK, Switzerland etc. for all their B48 and B58 engines.
Most European 'performance oriented cars' run on 0W-30/5W-30 or even 0W-20
oils today. Things did change recent decade.
I think its well established that the recommendations in the manual are not solely
written with engine longevity in mind but that the EPA letters to manufacturers play
a significant role.
Any prove for that thesis or just conspriracy?
.