2008 Ford F-250 Super Duty Spark Plug Replacement Guide

Maintaining your vehicle is an incredibly rewarding task and learning how to replace your spark plugs is a great place to start. There’s a decent probability you will be required to replace your worn out spark plugs several times while you own a a 2008 Ford F-250 Super Duty. Spark plugs are one of the most vital components inside your engine as they start the entire combustion process that starts and keeps your engine running for many thousands of miles. Like most engine components, spark plugs experience wear over time and eventually need to be replaced, but fortunately this is a repair you can do yourself. Chances are, if you’ve found yourself here, you have no idea how to do that, or maybe you’d just like to know what kind of spark plugs you need to buy. The complete process of changing your spark plugs should take approximately 20-45 minutes. This article will go over everything you should need to know about your Ford F-250 Super Duty’s spark plugs, whether you need some baseline information or a full, step-by-step guide to performing a spark plug change.

Correct spark plugs on a 2008 Ford F-250 Super Duty

CHAMPION 7406[/caption]For any 2008 Ford F-250 Super Duty, you can use CHAMPION 7406 spark plugs. These will be an exact fit and will match the required specifications of your engine. Make sure you purchase the correct amount of spark plugs for your engine corresponding to the number of cylinders. Occasionally manufacturers will bundle spark plugs in quantities that make it impossible to buy the exact amount you need for your engine. In this case, it is not a bad idea to purchase enough for your next two spark plug changes just so you will always have a new set ready to go. We always try to recommend the best possible spark plugs for the money, and these spark plugs are either a factory recomendation or an equivalent replacement available in today’s market at an affordable price.

How often should I change my spark plugs?

Very generally, it is advised that you replace spark plugs once every 20,000 to 40,000 miles. Of course, please make sure to check your owner’s manual to determine the exact interval determined by Ford for the 2008 F-250 Super Duty. Of course, if you drive your vehicle more aggressively or own a F-250 Super Duty with some modifications, you may want to consider changing your spark plugs closer to the 20,000 miles end of that spectrum.

However, there are also telltale signs of a car that may need a spark plug replacement prematurely, such as:

  • Engine misfiring
  • Rough idle
  • Problems starting your engine

Note that this list is certainly not comprehensive, and these problems on their own do not necessarily point to the spark plugs being the solitary culprit. However, the best way to prevent any issues with your vehicle is to take care of it with regular maintenance, and you are definitely doing so with the responsible decision to replace your Ford F-250 Super Duty’s spark plugs on a regular basis.

Changing spark plugs on a 2008 Ford F-250 Super Duty

This is a process you should be able to do on your own with some standard garage tools. Of course, consult your owner’s manual, as well as a factory service manual or an equivalent Haynes or Chiltons manual. The video shown below does a good job of outlining the process.

Helpful Tools

While not totally necessary, a spark plug tester is something you may want to invest in.
As noted before, you should be able to do a spark plug change with some regular tools you most likely already have. However, there are a few tools that are specific to this job that you may not have, and we also want to recommend some general tools that you should for sure have in your toolbox if you don’t already.

  • A torque wrench is a essential tool to have in your collection. You should check your FSM (factory service manual) or owner’s manual to determine the correct torque rating to use when installing the new spark plugs for your 2008 Ford F-250 Super Duty to be confident they are installed properly.
  • A spark plug tester – this is definitely a niche tool, but it can save you lots of time. Although we’ve discussed spark plug replacement being a good thing to replace regularly and not just when issues occur, you may also be replacing your spark plugs because of an issue. This tool can help you diagnose the exact problem.
  • A set of spark plug sockets – These come in extremely handy because many standard sockets are not deep enough for spark plugs. In addition, some spark plug holes are a bit smaller, so it requires a thinner wall like the one featured in the product here to fit. The linked product also features a magnet to keep a good hold of the spark plug so you do not drop it into your engine bay!
  • A spark plug gap tool. This allows you to check the gap of your spark plugs and increase or decrease it if necessary. Most plugs will come pregapped, but if this is not the case, you should definitely have one of these.

Tips for changing spark plugs on your 2008 Ford F-250 Super Duty

It is a great idea to have some dielectric grease handy.
Be sure to watch the video above before you attempt to repair the spark plugs on your 2008 Ford F-250 Super Duty, as well as review your FSM (factory service manual). Also, see the tips included below here to help you as you complete this repair.

  • It isn’t a bad idea to use dielectric grease when installing new spark plugs. You can apply a a little bit to the inside of the boot and the ceramic part of your spark plugs. It prevents voltage leak and helps avoid the misfortune of the boot fusing to the spark plug over time.
  • First, disconnect the negative terminal of your battery. You should always disconnect the battery anytime you work on the electrical system of your Ford F-250 Super Duty or any other vehicle.
  • Note that this is not official advice as many spark plug manufacturers advise against the use of anti-seize. However, I have heard from numerous old-school mechanics that they always apply a tiny amount of anti-seize to the threads of their spark plugs, especially on older vehicles.
  • During this process, one of the most vital things to ensure you do is to avoid overtightening the plugs or worse, cracking them due to overtightenting. Use a torque wrench capable of lower, more precise torque ratings to be sure that you don’t make this mistake.
  • Your engine should be completely COLD before you replace your spark plugs. You should wait at least 30 minutes after your engine has been running before attempting to replace the spark plugs on your 2008 Ford F-250 Super Duty

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