Castrol Magnatec OCI

[supercity]

I have 2 old Nissans with SR20 engines in the family that are currently running on Magnatec 10w40. I've only ever used whatever dino was on special, usually GTX, before this at 10,000km intervals. Could I extend the OCI on this oil past 10,000km?

 

[dparm]

What sort of driving habits?

 

[supercity]

Mostly city driving, general commuting.

 

[Garak]

It's certainly possible, but I'd run a UOA to be sure. I've done 10,000 km on conventional with almost 100% city driving, but that was LPG (i.e. no fuel dilution) and taxi service (i.e. no cold starts and oil always up to temperatures).

 

[supercity]

Thanks Garak. That is of course the sensible answer however it is uneconomic and impractical to do a UOA in this case. Magnatec is described as part synthetic but I suspect is is not significantly different to the average conventional lube these days.

 

[Garak]

Well, at least you have the climate in your favour. You're not doing a bunch of below zero cold starts and then hoping the oil warms up reasonably well to cook off any moisture or fuel dilution. If those engines don't impart a lot of fuel dilution in the first place and your city driving and commuting isn't too short, it might not be much of an issue.