Atlanta_man
New member
104,000 miles
Got it done today with NGK (3764) BKR6EIX-11 Iridium IX's (the mid-price of the three NGK Iridium part numbers that are specified for the 2005 4.7 V8, $7/each <well one of the three was platinum only and the high end was combo Irid/Plat>). Originals were all Denso's.
None of the old plugs was very tight, all came out easy. Way too easy in fact. Only one had a bit of a dry squeak during a couple the unscrew turns on the way out.
Looks like the spark plug ads that tout the special metal coating on the threads to prevent problems in alloy heads is true.
All the plugs looked good on the business end, around a mm or two of gap wear, and some slightly discolored but clean internal insulators.
One plug had quite a bit of hard black deposit on the outside body above the threads and its coil's plug boot had some of the same deposits on it. Looked like black plastic, and it would not clean off the plug short of a hammer and chisel.
The boot cleaned up OK with some alcohol but the boot itself is a nice brown color rather than that factory blue gray of the 7 others. Clearly some amount of blow by has been going on at this plug for a long time due to the lack of sufficient tightening at the factory.
The only lesson learned from the plug change itself was to be sure to snap the 4 conductor connector on coil pack before screwing it down. Otherwise it tries to get between the coil module and the engine. Good light would be helpful too.
Got it done today with NGK (3764) BKR6EIX-11 Iridium IX's (the mid-price of the three NGK Iridium part numbers that are specified for the 2005 4.7 V8, $7/each <well one of the three was platinum only and the high end was combo Irid/Plat>). Originals were all Denso's.
None of the old plugs was very tight, all came out easy. Way too easy in fact. Only one had a bit of a dry squeak during a couple the unscrew turns on the way out.
Looks like the spark plug ads that tout the special metal coating on the threads to prevent problems in alloy heads is true.
All the plugs looked good on the business end, around a mm or two of gap wear, and some slightly discolored but clean internal insulators.
One plug had quite a bit of hard black deposit on the outside body above the threads and its coil's plug boot had some of the same deposits on it. Looked like black plastic, and it would not clean off the plug short of a hammer and chisel.
The boot cleaned up OK with some alcohol but the boot itself is a nice brown color rather than that factory blue gray of the 7 others. Clearly some amount of blow by has been going on at this plug for a long time due to the lack of sufficient tightening at the factory.
The only lesson learned from the plug change itself was to be sure to snap the 4 conductor connector on coil pack before screwing it down. Otherwise it tries to get between the coil module and the engine. Good light would be helpful too.
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