Gen 2 & Gen 3 Raptor 3.5L EcoBoost Spark Plug Replacement (2017+)

Who this is for

This is for the 3.5L EcoBoost shared by the Gen 2 (2017–2020) and Gen 3 (2021+) Raptor. Ford's own line on this job is direct: "for spark plug replacement, contact an authorized dealer." We're covering it here because plenty of experienced owners do take it on themselves, but go in knowing it's a longer, more involved job than an oil change or a filter swap — the video on this page runs twelve minutes even edited down, and it covers removal, gapping and installation on a 2021 Gen 3, noting the process is basically the same across Gen 2, Gen 3 and the Gen 3.5 refresh. If you're not comfortable working this deep into the intake and ignition system, Ford's advice to see a dealer is the right call, not just a disclaimer.

Steps

1. 1

   Know what you're taking on before you start

   Ford's own guidance for this job is to contact an authorized dealer. This write-up is for owners who are comfortable going ahead anyway, not a replacement for that advice — if anything about accessing the coils or plugs on your specific truck doesn't match what you expected, that's a good moment to stop and reconsider rather than push through.

2. 2

   Let the engine cool completely

   Work only with a cold engine. Besides the obvious burn risk, removing a plug from a hot aluminum head raises the odds of damaging the threads — something you really don't want to deal with on this platform.

3. 3

   Confirm the correct plug and gap for your model year before you buy anything

   The Motorcraft part number and gap spec actually change by year: SP-534 at 0.030–0.033 in for 2017, SP-578 at 0.028–0.031 in for 2019, and SP-596 at 0.028–0.031 in for the Gen 3 2022 manual. Buy the correct plug for your truck rather than assuming one part number covers every year.

4. 4

   Work one cylinder at a time

   Don't pull every coil and every plug at once. Disconnect and move aside the coil pack for a single cylinder, do that plug completely, and move to the next — it keeps you from mixing up coils or losing track of which plug well you're working in on a six-cylinder layout buried under intake plumbing.

5. 5

   Blow debris out of the plug well before removing the old plug

   A quick blast of compressed air (or a brush, if that's what you have) around the top of the spark plug well before you pull the plug keeps dirt and debris from falling into the cylinder once the plug's out — a real risk on an engine that sees any off-road dust.

6. 6

   Remove the old plug

   With the coil clear and the well cleaned out, remove the old plug with your spark plug socket and extension. Set it aside — if you're curious about its condition, a quick look at the electrode can be informative, but don't read too much into it without a baseline for comparison.

7. 7

   Check and set the gap on the new plug

   Even a plug sold pre-gapped is worth checking against your year's spec before it goes in — 0.030–0.033 in for the 2017 figure, 0.028–0.031 in for both the 2019 and Gen 3 2022 figures. Use a gapping tool rather than eyeballing it.

8. 8

   Install the new plug and torque it to your service manual's spec

   Thread the new plug in by hand first to avoid cross-threading the aluminum head, then torque it with a torque wrench to the figure in your own service manual — this is not a spec we're going to guess at here, and it's exactly the kind of thing that goes wrong quietly if you just "snug it down."

9. 9

   Reinstall the coil and repeat for the remaining cylinders

   Reconnect the coil for that cylinder, confirm it's seated and latched, then move to the next cylinder and repeat the whole sequence. Working through them one at a time, start to finish, is slower but far less likely to leave you with a mismatched connector or a forgotten plug.

10. 10

    Decide where you stand on stock vs. colder plugs

    The video this page references installs a one-step-colder Ford Performance plug, which is a choice some tuned trucks make and is outside Ford's factory spec for a stock engine. If your truck is unmodified, the Motorcraft part number for your year is the one to run. If you're tuned and considering a colder plug, that's a decision to make with your tuner, not something this guide is positioned to recommend.

Specs

Safety notes

• Ford's own recommendation is to have an authorized dealer perform this job — only take it on yourself if you're genuinely comfortable with intake and ignition work on this engine.
• Work only with a cold engine.
• Torque each plug to the spec in your own service manual with a torque wrench — overtightening in an aluminum head risks stripped threads.
• Blow debris out of each plug well before removing the plug to keep dirt out of the cylinder.
• Work one cylinder at a time to avoid mixing up coils or connectors.