I READ your comments about the use of an additive with Optimax in a 1984 XE Fairmont. I have a new Territory and I am using Optimax. Should I use an additive as well?
THE short answer is no, you shouldn't use an additive. The Territory has been developed to run on unleaded, so using straight Optimax is fine. An additive is needed only for cars built before 1986 and developed to run on leaded petrol. The additive provides protection against valve-seat recession, something the lead provided.
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