Spark Plug Maintenance Schedule, miles or time? -
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Unread 03-14-2009, 11:52 AM   #1
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2002 WJ 
Join Date: Mar 2007
Location: Chicago Area, IL
Posts: 16
Spark Plug Maintenance Schedule, miles or time?

I had the spark plugs on my 2002 4.7L HO replaced by the dealership on March 2007 at 77K. As far as I know, those plugs in there were the originals, I bought the rig used at 72K.

According to my service information, the plugs should be replaced every 30K or 2 Years. I'm at 92K right now, so I have put only 14K on the current set in 2 years (It only drive it a few times a month or so).

Even though its been 2 years I don't feel at all like the plugs need to be replaced yet. Personally I feel the plugs can go by more of a milage basis instead of time, so I was going to wait until they have a good 30K on them. Would you agree?

Also, I took it to the dealership to do the plugs because the rears looked difficult to get to, they charged in the neighborhood of $250 parts/labor for the replacement. The plugs themselves are relatively cheap, so if the rears are not as hard to do as I'm thinking they are, maybe I should attempt to do them myself the next time?


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AdamJ is offline   Reply With Quote
Unread 03-14-2009, 12:06 PM   #2
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Join Date: Nov 2004
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Mileage. Save some money and change yourself. They aren't difficult to change, but I use an air compressor to blow out the tubes before removing the plugs, and after applying never seize, I use a small diameter rubber hose attached to the top to get the plug started. Easier feel than the deep socket, just to avoid any cross threading possibility.

Here's some reading:
Turbonut is offline   Reply With Quote
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