I did this for the first time today, with 140,000km on the truck (2004). Took 2 hours start to finish, could probably do it much faster next time. I ran two bottles of Redline SI-1 fuel system cleaner through the tank before attempting this job. All plugs came out no problem! I bought the special spark plug socket/extension for this engine and was very happy with it. Only needed a 3/8 impact swivel for the two back plugs w/ the impact, and a 2" extension to fit the impact driver. I did the first few with a pneumatic impact, then switched to an 18V cordless Makita impact driver that worked just as well and was an easier fit. Thanks for the guide and tips, saved me several hundred dollars easy.