The Ford Bronco is back — and it's captured the hearts of off-road enthusiasts across the country. Whether you own the new sixth-generation Bronco or a classic first-gen, here's what to run in the engine.
New Bronco: 2.3L EcoBoost
The base Bronco engine is Ford's proven 2.3L EcoBoost four-cylinder. Motorcraft SP-520 plugs are the OEM specification — engineered specifically for the EcoBoost's direct injection and turbocharging. Service interval: 60,000 miles. Do not skip this on a vehicle that sees hard off-road use.
New Bronco: 2.7L EcoBoost V6
The optional twin-turbo 2.7L V6 brings significantly more power to the Bronco. Motorcraft SP-546 plugs are the OEM spec for this engine. The twin-turbo setup demands quality plugs — misfires under off-road wheeling conditions are both annoying and potentially damaging.
Off-Road Driving and Plug Health
Low-speed trail crawling is hard on spark plugs. The engine loads up at idle-level RPMs, creating conditions that can foul plugs faster than highway driving. If you wheel your Bronco regularly, inspect plugs at 30,000–40,000 miles even with a 60,000-mile OEM spec.
Classic Bronco (1966–1996)
Classic Broncos with the 302, 351, or 400 V8 use copper plugs on shorter intervals. Champion copper or Autolite copper plugs are period-correct and reliable for these carbureted engines. Replace every 15,000–20,000 miles.
Shop Bronco spark plugs at Texan Supply with free shipping.