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  #25  
Old 04-04-2011, 02:56 AM
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Re: Spark Plugs

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Originally Posted by jas32 View Post
Changing spark plugs per factory recommendation is very very important particularly if these are original equipment plugs. They do not use platinum tips so there is not much leeway in terms of plug life and gap erosion. Typically, factory installed platinum tipped plugs usually have a 100k mile replacement recommendation.

Instead of replacing them with OEM plugs, I usually specify double platinum plugs (platinum pads on the tip and electrode), just so I have some leeway on mileage, if I do not get to replacing them right away. These just cost slightly more but well worth it. It gives you more consistent performance over time since the plug gap remains constant and does not change over time.

One more thing, make sure you put a dab of anti-seize compound on the threads so next time you have to do it, the plugs will come out cleanly and easily.
As I have suggested, Using factory plugs is always suggested, but if not thats your thing.

What I really commented on is the fact that EVERY sparkplug manufacturer states that you should not put anything on the threads of sparkplugs, furthermore I have replaced alot of them and NEVER have problems, if the car has 30k miles or 280k miles.
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  #26  
Old 04-06-2011, 03:33 PM
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Re: Spark Plugs

Im pretty sure that the factory recommends everything to be done at the factory... thats why they charge ~450 bucks for spark plugs and a local mechanic will only charge ~150. Shit... if i was the factory i'd say the same thing... all the Stealership wants is to make $$ so it covers their a$$e$ on the back end for all the warranty work they do.

i didnt get my spark plugs from Jeep... and they work GREAT... so far no problems and i paid 1/4 the price.
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  #27  
Old 04-06-2011, 05:43 PM
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Re: Spark Plugs

I had a 2006 Laredo with the 3.7 and put over 60k miles on it and didn't change the plugs once. Car ran great and I averaged about 16-17MPG with over-sized tires. I never even looked to see what the service interval was. Shame on me...but I got away with it.

Now that i think about it, i'd like to see what those spark plugs looked like.
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  #28  
Old 04-18-2011, 09:32 PM
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Re: Spark Plugs

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Originally Posted by kkuty View Post
I had a 2006 Laredo with the 3.7 and put over 60k miles on it and didn't change the plugs once. Car ran great and I averaged about 16-17MPG with over-sized tires. I never even looked to see what the service interval was. Shame on me...but I got away with it.

Now that i think about it, i'd like to see what those spark plugs looked like.
Interesting that plug wear seems to differ from engine to engine/vehicle to vehicle. My daughter's plugs on her 07 3.7L Liberty was well worn when I replaced them at 30K (opened up to .050-.060 gap), while my wife's 08 3.7L WK was pristine at 30k miles. Going over 30K miles with non-platinum tips is always risky as you cannot always tell how things are going on inside the combustion chamber.
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  #29  
Old 04-18-2011, 09:40 PM
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Re: Spark Plugs

I do mine every 10-15k miles just because.
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  #30  
Old 04-18-2011, 10:00 PM
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Re: Spark Plugs

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Originally Posted by 2005JGC View Post
As I have suggested, Using factory plugs is always suggested, but if not thats your thing.

What I really commented on is the fact that EVERY sparkplug manufacturer states that you should not put anything on the threads of sparkplugs, furthermore I have replaced alot of them and NEVER have problems, if the car has 30k miles or 280k miles.
Good suggestion to always use factory parts. However not all factory parts are better than aftermarket particularly spark plugs (brakes are another). Not really that it's "not my thing" in using factory parts, I just know there's something that will perform much better and give me a bit of time if I can't get to it right away (e.g. I hate working on my car in the middle of winter), all for a very small incremental investment without any effect to the engine's performance.

Although it rarely happens. a small amount of anti-seize compound is just cheap insurance to prevent freezing your plug in an aluminum head. Imagine what kind of problem you have if you strip the treads on an aluminum head (can you say helicoil?). This was not a big problem in the good old days when all cars had cast iron heads. I have not seen any negative effect on using the compound.

Of course if you change your plugs every 15K, using platinum tipped plugs and anti-seize compound would be overkill.
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  #31  
Old 04-19-2011, 11:36 AM
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Re: Spark Plugs

I just changed the plugs in my wife's 2006 3.7 WK. She was at 70k with the originals, and started noticing a RPM drop at idle when the truck was warmed up. when i took out the original plugs the gap was around .65 for most of them :-( The back , passenger side one was not that hard to take out. I didnt use wobble extension, jsut a regular 6 inch extension. I used dielctric greas on the o-rings of the packs, as well as on the ceramic portions of the plug to create a nice seal on the rubber boot. I also used a torque wrench to tighten all the plugs down to 20ftlbs...this is somewhere you dont wanna guess at. oh..and i just used NGK plugs.
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  #32  
Old 04-22-2011, 12:41 PM
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Re: Spark Plugs

From what I've heard in regards to HEMI engines, you either use the factory original copper Champions or the aftermarket Iridium ones. The engine doesn't seem to like the Platinum or Double Platinum plugs.

I have not verified anything myself though but I'm planning to change the 8 plugs below the coils to Iridium and see how it performs. I'd leave the other 8 (exhaust spark) stock.
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  #33  
Old 07-25-2011, 09:25 AM
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Re: Spark Plugs

OK, it's been a few months since I replaced the spark plugs, 8 iridium on compression stroke and 8 standard copper on exhaust strokes.

There's is a noticable difference. You can't go wrong with Iridium.

I'm thinking of modding the setup a little bit by removing the leads to exhaust strokes. I want to shorten them and have each coil firing up both spark plugs at the same time during the compression stroke. I don't think that any raw fuel would escape that.

Anyway, from now on, Iridium all the way.
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  #34  
Old 07-25-2011, 10:24 AM
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Re: Spark Plugs

I changed plugs on my 06 WK a couple times and on my 07 WK the day after I bought it.
The linked video is how I figured out the first change. Really is a piece of cake - just take your time. I usually clean my engine compartment before changing them. It keeps a clean engine compartment, plus makes the job less messy. While you're at it you may as well change your air filter as well. When you take the main intake box off be sure to be gentle with it and keep anything away from the MAF.

Take pride in doing work on your own vehicle - does a body good.
Good Luck!
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  #35  
Old 07-25-2011, 12:10 PM
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Re: Spark Plugs

Quote:
Originally Posted by timelessr1 View Post
I just changed the plugs in my wife's 2006 3.7 WK. She was at 70k with the originals, and started noticing a RPM drop at idle when the truck was warmed up. when i took out the original plugs the gap was around .65 for most of them :-( The back , passenger side one was not that hard to take out. I didnt use wobble extension, jsut a regular 6 inch extension. I used dielctric greas on the o-rings of the packs, as well as on the ceramic portions of the plug to create a nice seal on the rubber boot. I also used a torque wrench to tighten all the plugs down to 20ftlbs...this is somewhere you dont wanna guess at. oh..and i just used NGK plugs.

Right on the mopar spark plug box it gives a torque angle. If there is a crush washer I think it says 1/4 turn or 1/2 turn after seating the plug, and without the crush washer it says 1/16th of a turn... I have never had any problems using this method of torquing.
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