I have a 2004 F150 with 25,000miles on it. I want to replace the plugs (age, not mileage) but have been told by several people that this risks stripping the threads in the heads requiring head replacement. Ford says they have no service bulletins or recals on this. Anybody else have this problem?
I didn’t know that there is an aging problem with spark plugs. If your engine doesn’t have a spark miss, I would leave them alone. Our 2003 Toyota 4Runner has, I think, an aluminum engine. I had the plugs replaced last summer at the 60,000 mile mark. I was worried about the same thing that you are, but I had my trusted independent shop do the work and there were no problems.
A torque wrench is a good investment for anyone doing their own work on an engine. You can get a decent one for under 30 bucks and it can save you a lot of headaches. If you dont do regular auto repair, you will enjoy the confidence you get from this tool, because your ablity to gauge when a nut bolt or plug is tight may get rusty between jobs.
Check your repair manual for the proper torque spec. and tighten accordingly. As for the need to do this, has your mileage or oil consumption changed recently? Is there any reason why you want to change the plugs besides a while hare? As far as cross threading, you want to get the plug in straight, and turn it snug by hand before you put any torque on it.
This is a common problem with the Ford Triton Engines. Once you remove the coil, look down inside the hole where the plug resides, if you see rust or corrosion, pour in some GOOD penetrating oil. Carefully remove the plug afer 24 hours. With only 25,000 miles I would not worry about the plugs. I had a 2000 E-350 that I drove 322,000 miles with the original plugs!! (No Kidding). It was a company truck and I wanted to see how long it would go on the plugs. I kept all other parts serviced, but the plugs were still doing fine when I traded the van for a new one last December.
It used to be a common problem. When the modular engines got the P.I. heads circa 1999-2001 depending on the model. The spark plug ejection problem was largely fixed. A 2004 model F-150 won’t have that problem. Keep in mind if you have a 5.4L it’ll take kind of an odd-ball sized spark plug. Use a torque wrench and put some anti-seize compound on the threads.