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wayneh20
By wayneh20 | AA Member | 5 Posts | 3 January 2013 at 2:06pm

I am considering buying a Toyota Mark X either a 2.5L V6 or a 3.0L V6. Both vehicles are direct injected. I am getting mixed responses when I ask about the grade of petrol I should use. Before making a purchase decision I need to be very clear about this. Do these vehicles require 98 Ron or can they run on 95 Ron. I understand that 91 is not an option. Can someone give me a definitive answer please?

Anon
By Anon | Community Member | 4 January 2013 at 10:53am

Toyota Mark X’s use engines out of the Toyota “GR” family.
Our research shows early Mark X’s (up to October 2009) to be fitted with 2.5lt or 3lt engines and later ones with 2.5lt or 3.5lt, all are V6.
3lt engines are 3GR-FSE
2.5lt engines are 4GR-FSE
3.5lt engines are 2GR-FSE (The FSE designates direct injection)
The later 2.5lt has a compression ratio of 12 : 1 and the 3.5lt 11:8 : 1.
Early high compression engines are designed to run on high octane (98 RON). As technology evolved, it became possible to run these high compression engines on low octane (91 RON). (Mazda’s Skyactive engines run 91 octane with a compression ratio of 13.5 : 1 without any pre-detonation).
The manufacturers recommended octane rated fuel should always be used.
If this information is not available from Toyota, we recommend to run the early versions on 98 RON and the late ones on 95 RON.

wayneh20
By wayneh20 | AA Member | 5 Posts | 4 January 2013 at 2:29pm

Thank you for this very comprehensive reply