What a difference 16 new plugs make

[fuzzy94]

When I bought my commander in Feb it had 54k on the odometer. I just changed the plugs yesterday at 58500mi (stock Champion Copper 570) and wow what a difference in acceleration. The plugs I took out were original, so I guess Mopar was right recommending the plug change at 60K.

Thanks to this forum for letting me know to stay away from any platinum and other style plugs. Definitely saved me a headache

[PolarBZ]

If you keep track, how have the new plugs affected your MPG? I'm a bit overdue for changing my plugs and am getting crappy gas mileage. I'm thinking they could be related.

[fuzzy94]

I was averaging 13.3 before. Since changing the plugs Im seeing 14.4 same mileage back and forth to work, so its been better.

I've noticed the type of gas makes a difference too. I usually go with shell or exxon but I filled up with Delta one week and my MPG dropped to 11 mpg

[mrnavy2]

I have a 08 XK 4.7 and i am wondering if all 4.7 have 16 spark plugs?

[jeep5253]

Originally Posted by mrnavy2

I have a 08 XK 4.7 and i am wondering if all 4.7 have 16 spark plugs?

No.

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[Cloud6221]

I'm at 54k right now, so I was going to change mine too. The owner before be had already changed them to high output platinums. So now I have a set of 16 spark plugs for a hemi sitting around. What's this about staying away from platinum? Should I get a set of coppers or iridiums? I figure I'll change them at 90-100k.

[mrnavy2]

@Jeep5253 so what would be the best way to fine out if mine has 16 plugs? Thanks gaIn for all your Help. Steve

[jeep5253]

I think the 4.7 went to 16 plugs with the '08 or '09 models. Whichever year they made the changes to the 4.7. Best way to find out what you have would be to open the hood.