Oil question

Post Mon Nov 13, 2017 1:39 pm

I order 8 litres of good old Castrol GTX semi synthetic 10W40 from CP4L but received Castrol "ultraclean" 10w40 fully synthetic. Is this still ok to use in my '89 325i?

Post Mon Nov 13, 2017 2:28 pm

I've just started using this stuff and it's already reducing the slight piston-slap my engine had.
Can only think that a piston-ring or two were semi-stuck and this stuff is gradually cleaning the crap from around the rings.
Also under the cam-cover is v. clean 'cept for the usual varnish-colour and even that is starting to dissipate.
So it's a thumbs-up from me.

Post Mon Nov 13, 2017 7:07 pm

A full synthetic is always going to be superior to a semi synthetic. Why wouldn't it be?

Post Mon Nov 13, 2017 7:57 pm

Brianmoooore wrote:A full synthetic is always going to be superior to a semi synthetic. Why wouldn't it be?

No idea, that's why I asked. Thanks for the replies, I wasn't looking forward to returning it.

Post Tue Nov 14, 2017 12:08 am

Castrol Ultraclean 10w40 4L is now down to £16 at Asda stores.

Post Tue Nov 14, 2017 12:30 am

My machine shop bloke hates synthetic oils. Only uses mineral oils.

Post Tue Nov 14, 2017 9:36 am

drakesmith wrote:My machine shop bloke hates synthetic oils. Only uses mineral oils.

More engine wear = more work for him.

Post Tue Nov 14, 2017 10:26 am

What are your thoughts on Millers Oils Brian?

http://www.millersoils.co.uk/automotive ... ls/premium