NGK (3403) TR55GP G-Power Spark Plug, Pack of 1

My vehicle is a 2003 Ford Expedition with the 5.4L V8 that had 118K on the odometer. I started experiencing lack of power and buckling under load while on the hwy at about 70 mph and while in overdrive. I'm a 30 year veteran master mechanic. Needless to say I was somewhat skeptical about this set but read all the reviews and decided to give them a shot. After install along with new coil packs (DG508) the engine had at least a 25% increase in power. It was like night and day and I was just blown away! I have now put about 1500 miles on these spark plugs and they are fabulous and have been working perfectly. Buy these new spark plugs and you wont believe the horsepower increase!

Great brand, great plugs. Their design has changed in mid 2023 to further prevent the platinum element breaking, but in my case it's totally fine to use both the "old" design and the new design together, confirmed by NGK Technical Support.

I wont know until the vehicle gets 60k miles on it, but they fit well and fire well. I am Very Satisfied with these so far.No more misfires when hot, and the Buick now runs like a charm.

2010 Ford E350 XLT 12 passenger van, 5.4L V8... I hate trying to figure out what vehicle people are installing parts on...Parts arrived on time and in good condition. Upon installation, I compared the two boots—old and new—and the new ones were indeed longer by over 1/4". (I did NOT CUT THEM) Luckily my old boots came out dry (no oil seepage into spark plug wells) so I swapped out the boots. It was very easy to swap them out, but be careful not to stretch the coil spring...Plugs were pre-gapped to .054" the spec for my vehicle as advertised (I checked every one)WATCH THIS VIDEO FIRST:FordTechMakuloco on you tube has an excellent installation video for clearing the front of the engine compartment and removing the internal engine cover (doghouse) before starting the project and another video on the actual spark plugs and coil replacement.SKILLS NEEDED:This is beginner to intermediate skills weekend warrior mechanic friendly. It ain't "easy" but it ain't "hard" either. Go slow, meticulous and keep referring to the video above.TOOLS Needed:Spark plug gap tool - if you're doing spark plugs at the same time.3/8" driver wrench3/8" torque wrench (only if you're replacing spark plugs also. Though I have no idea why you'd go to the trouble of accessing and removing the coils without replacing $30-35 worth of spark plugs.6" 3/8 extension - These two are to remove spark plug3" 3/8 extension - to remove spark plug1/4" Driver wrench - to remove air intake hoses and the bolts holding down the coils5/8" spark plug socket (the one with the rubber boot that grabs the spark plugs) - Once again if you're doing the sparkplugs.7MM socket - Coil bolts8MM socket - Air intake hose hold downs.Air compressor with blower or a can of compressed air... (for blowing out the spark plug wells) - Trust me, there was tons of dirt/dust down my spark plug wells.SUPPLIES:Shop ragslatex glovesSilicon dielectric grease (Not clearly stated on this product is the fact that the coils come with two silver "sugar-packet sized" packs of dielectric grease. This is for the bottom of the boots to protect the spark plug post where it connects with the coil. I used a little on the coil electrical connections and the injector connectors also.TIPS:REMOVE all the air intake stuff to access the driver's side row of coils/spark plugsI removed the PCV valve to move the hose out of the way of the passenger bank of coils and spark plugsCHECK the length of your old coil boots before installation to make sure of the length. If your old ones are shorter and in good shape, don't cut the new ones, just swap them out like I did.Spark plug gap on 5.4L for my vehicle - .054"FordTechMakuloco suggests over-torquing the spark plugs from manufacturer's spec of 12-15 up to 20 foot pounds to stop spark plugs from backing out due to thin thread depth in the engine heads. This is to stop the plugs from blowing out. (3 of my old spark plugs were already backing out—very loose)I pulled all of the injector connectors and coil connectors on the entire bank/row of spark plugs and coils—first Driver's side (the easiest), then passenger (a little more challenging). This made accessing things with a wrench MUCH easier.Driver's side - I did the front 2 from the engine compartment and the rear 2 from inside the van.Passenger side - From 2 from engine compartment, rear 2 from inside vanTEST DRIVE:Slow for a few miles and I could definitely tell the difference in power. Whether it was spark plugs or coils, I don't know and don't care.Hamered it on the freeway and about 25% more power over the burned up old plugs and the old coils.Bottom Line:Several minor cuts, bumped knuckles and some cursing and it took me about 2-3 hours with cell phone interruptions.I did the coils because I was already in the engine to do the spark plugs at 90,000 on my van. Spark plugs were HORRIBLE with a huge gap and all burned up. Didn't surprise me as I'd noticed a serious lack of power. I used the cheap NGKs for my van found here on Amazon and these coils. After installation, my test drive was awesome.I couldn't believe that 90k the spark plugs were toast, however I tow a boat with this vehicle so it's under some stress on long trips and its a stop and go soccer van during its everyday driving.

Great plug even for domestic vehicles. Fires up immediately and keeps a good idle. Fuel efficiency is on par with performance.

It's a spark plug. It's cheap. It works. Don't over think an OEM spark plug replacement. Just buy it. And don't go to an auto parts store or they will talk you into a qaudra titanium double diamond triple gold plated plug your car doesn't even need.

These plugs are good plugs for the money my car is running great. However the delivery has a lot to be desired, kept getting a we came by and no one was home try to deliver tomorrow anyway they need to do something about fed-ex smart post as it is slower than snail mail

I'm sure the spark plugs are very good. We ordered the NGK 3403 based on the recommendation of Amazon as one that fits our pickup. When we put in all the info about the truck and they come up with these as an option, we expected accuracy. They are the wrong ones. Yes, we are partly at fault for not checking further, but I write this to tell others that you need to be sure to check elsewhere before purchasing. We foolishly believed the information was accurate and ordered. We won't do that again.