We changed the plugs, well 7 of them anyway because we'll you'll see. Please make sure your engine is warm when you try to remove the plugs. You can also spray a little blaster inside the spark plug tube. Another thing you can do is run a can of seafoam inside the fuel tank before you do the job to help break up any carbon buildup that may be on your plugs. We purchased a set of Motorcraft replacement plugs and MAS Coils via Amazon. The coils were crap. Here's what happened. MAS Set of 8 Ignition Coils DG511 and Motorcraft SP515 SP546 Spark Plug Compatible with Ford Lincoln Mercury V8 V10 5.4l 6.8l 3L3E12A366CA 5C1584 C1541 FD-508 DG511 RED DG-511 https://a.co/d/5sWpP3c Tools I would highly recommend: ARES 11010-3/8-Inch Drive by 9/16-Inch Magnetic Swivel Spark Plug Socket - 6-Inch Spark Plug Removal Tool https://a.co/d/eczFM1v Hopefully you never need this one because it's the tool you need to extract broken spark plugs: GSTP Spark Plug Extractor, Broken Spark Plug Remove Tool Kit Compatible with Ford Expedition F150 F250 F350 Mark LT 3 Valve Engines 5.4L https://a.co/d/aU2T66V Seafoam but I would just grab it at your local autoparts store: Sea Foam SF16 Motor Treatment 16 oz https://a.co/d/eRpPvuE Blaster a must have but also grab this at your local hardware store or auto parts store: Blaster 16-PB Penetrating Catalyst - 11 oz. https://a.co/d/haCDRLa