Are the Autolites any better than the OEM plug? I replaced my plugs at 30000 miles using the OEM Motorcraft plug. It was very difficult to remove them, I broke each plug loose by hand and then used some GM rust penetrate. After I let them sit for 10 minutes I turned each plug a 1/4 turn at a time until they came out. There was a good amount of carbon build up on the plugs. I haven't check the plugs since then and I am at 45000 miles. I was thinking of using the Autolites instead of the Motorcraft plugs.