What makes you think it needs new plugs? Having a misfire or other issue? Those are Iridium plugs that generally are 90-100,000 mile plugs.
The difference in plug numbers
SP-537 - Turbocharged 2.0.051 gap
SP-535 - Non-Turbo 2.0 .051 gap
Or just check on the tag under the hood.
The Ford service interval shows 60,000 miles for severe duty and then only with the turbo 2.0, Normal service shows 100,000 miles.
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Sunday, April 9th, 2017 AT 12:56 PM