GroundRat

Hey all,

BMW owner here: 2003 525i E39 (American spec, 186K miles, automatic trans, currently drive in Germany). Owners manual says use either 5W40 or 5W30 (in that order.) Currently using Castrol Edge 5W30 Full Synthetic; change oil religiously every 5 months or 5K miles, whichever occurs first.

Have read posts where owners talk about switching to 0W40 or 10W60 (on this site and other Pro-BMW sites). Some of these post are dated, but I'm interested in the current mindset of synthetic oils and engines over 15 years old.

Will continue using 5W30....would be interested in reading your opinions on switching to different grade (as listed above) or keeping inline with the manual's recommendations. Thanks all in advance!

V/r,
GroundRat

seanjordan20

I know I changed my oil to 0w40 when the car was about 5 years old and never looked backed. There was a slight ticking noise in the engine bay and after changing the oil it it never came back so I kept using 0w40.