MR2 3SGTE oil recommendation

[keith9849]

Just about to have a pre-MOT service and oil change on a 1989 SW20 3SGTE MR2 turbo, 70k miles. I have seen lots of people enthusing about Mobil 1, and Castrol Magnatec, and of taking the cold-viscosity lower, even on older engines. Any suggestions please?

I hope this doesn't start an argument!

[Red Devil]

I've owned several MR2 turbos over the last 11 years (from stock to 350+ bhp). I always use fully synthetic oil for its superior resistance to breakdown.
The temps in the feed lines to the turbo can easily cook a mineral based oil if you're not careful. Any resulting baked on deposits in those lines can be bad news.

You should be fine using Mobil 1 or Castrol Edge. However Magnatec is only a semi synthetic.*

 * Note that Castrol do produce a fully synthetic version of Magnatec but it is to ACEA A5 spec - http://www.oilspecifications.org/acea.php

ACEA said:

The A/B class's A5/B5 oils have lower HTHS viscosities, which means that they provide better fuel economy but they may not provide adequate protection in engines that are not designed for them.

ACEA A5/B5 was first introduced into the ACEA Oil Sequences in 2004, however, it is based upon the original ACEA A5 and ACEA B5 sequences that were introduced in 2002.
The 3S Toyota engine first saw the light of day 30 years ago long before the A5 spec came into existence. I would therefore be wary of using that version of Magnatec.

Just because something is newer doesn't automatically mean it's better in a given application. There are other considerations which need to be factored in.

[190bhp]

I use 10w40 millers competition CFS fully synthetic in my Rev 3 Turbo.

[Red Devil]

I know several people who use Millers.
Fuchs Titan Race Pro S 5W-40 in my Rev 5.