Bare in mind that I haven't done an engine tune-up since 1996, that was the last time I did a full tune-up on my 1985 Toyota 4X4 pickup that ended life getting rear ended and totaled in October of 1997. I replaced that truck with a '97 F-150 that came with 100,000 mile plugs, and since I only clocked about 35,000 miles on it before trading it in on an '02 Dodge Ram 1500 4X4 pickup there was no reason for me to break out the spark plug wrench. Traded in the Dodge in '05 for this Jeep Liberty Renegade, and again I didn't clock enough miles on the Dodge to bother with a tune-up.
Now that I've had this KJ for just under 5 years, and just under 30,000 miles....(most all of it stop & go city driving, or lugging through soft beach sand)....I decided to treat my girl to a new set of Autolite Double Platinum plugs...(APP-5224)

I've also been hearing a lot of horror stories about plugs getting stuck in the newer Ford engines, and wanted to change these out before any seizing issues started with these Chrysler 3.7's.....

Everything I've owned up to this point has been a breeze to do a plug change on, but these KJ's with the 3.7 Lt V-6's sure pose a challenge. Technically all one needs is a 5/8" plug socket, a 10mm socket, the ratchet handles to go with them, and a slotted screw driver to pull the air intake tube to access the plugs on the left side......or so I thought....
I wasn't aware Chrysler drilled a 3 foot deep well to sink their plugs into, now getting them out wasn't so difficult since I was using my Craftsman plug socket with the rubber tube insert that grips the plug, once the plug was free of it's threaded confines, out it came stuck in the socket.
The issue arose when I went to put the new plugs back in, and the socket got stuck on the plugs....(down inside the 3 foot deep well)....pulled off the extension bar and wouldn't come back out. Now I had to dig out a pair of long tip needle nose pliers, get a grip on the socket and yank it off the plug.
Now the right side of the engine isn't too bad, it's the left side that really took some thought and patients on my part. Had to remove the air intake tube, and figured that would do the trick....but nooooo....I also had to remove the cruise control bracket, and the anti-freeze reservoir so I could access those coils and plugs.
What "I thought" would take about an hour, took all morning, and by the time I was done almost every tool in my box saw daylight.....

The stock plugs were NGK's, I checked every one as I pulled them out, and every one was at a different gap, and none were even close to the recommended .035"....most were between .045" and .050"

The new Autolite's are at least starting their new life in my KJ's engine gapped at .035" ....and what a major difference they made, can't say if I'll be burning less gas, but the throttle response is amazing, and maybe I'm just a little nuts, but it feels like it gained some horsepower as well.....

A plug change is a major P.I.A. to do, but well worth the effort.....

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2005 KJ Renegade
3.7 Lt. V-6
2.5" Daystar Lift
Thrush Welded Muffler
K&N (Poor Man's) cold air intake
Goodyear Duratrac 245/75-16

Glad I didn't have those troubles, only thing I had to remove was the air intake hose. Took 20 mins or so. You'll probably be glad you did tho, I had 58XXX miles and when I swapped plugs I saw nearly 3mpg increase on the interstate!

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03' Renegade. Front Frankenlift II Premium,1 Conduit, Rear OME 948, Ranchos, Upper Iso, JBA 4.5 Arms, 16x7 4inch backspacing Black Rock Street Locks, 245/75/16 Duratracs. Lots of stickers.
WVU

easy way to keep the plug socket from sticking on the plugs is to put a small dab of anti-seize on the outside of the plug,no more stuck socket.

Thanks for that tip! I'm probably going to do mine this week. I don't want to have the same problems.

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Jason

2003 Red Wrangler Freedom Edition

2009 Black Grand Cherokee Rocky Mountain Edition

The only advice I would add is, if you DO lose socket down there and start struggling with it... be VERY careful about how frustrated you get when rattling around trying to get the socket back out. That's when plug ceramics get cracked.

Good call on the anti-seize, tjkj...

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-=Stock, but goin' places=-

04 3.7 Sport.
Auto Trans
Yokohama Geolandar AT/S 235/70/R16
Garmin GPS on RAM Mount

Mileage Trend:

I'll admit most of my problems were self inflicted.....half my tools were at work, and what I had at home to do the plug change wasn't exactly condusive to the job at hand....

I was using a 1/2" drive ratchet with a 1/2" to 3/8" adapter...should of had my 3/8" set with me.

I like the idea of using anti-seize to keep the socket from sticking to the plug, I also heard another idea on another forum....wrapping the socket to the exention bar with electrical tape.

I was careful yanking the socket out with the needle nose, making sure I pulled straight up, but I did skin a few knuckles doing it....

Now that I bumbled through this once, I'll have an easier time with it when I do it again.....

Thanks for the suggestions......

_________________
2005 KJ Renegade
3.7 Lt. V-6
2.5" Daystar Lift
Thrush Welded Muffler
K&N (Poor Man's) cold air intake
Goodyear Duratrac 245/75-16

Just trade it in for a CRD and you will have no more spark plug issues.

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2006 Liberty CRD Limited Deep Beryl Green Metallic Clear coat, Fumoto valve, MH ProVent (removed), GDE Eco tune,
OME 790/948 springs, OME struts, OME N132L shocks, Jeepin by Al A-arms, Hercules Terra Trac AT2 245/75R16
Weeks Stage 1 EGR delete, 5 volt steel glow plugs

And I hear-tell you receive a whole bunch of New and Improved(tm) problems!

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-=Stock, but goin' places=-

04 3.7 Sport.
Auto Trans
Yokohama Geolandar AT/S 235/70/R16
Garmin GPS on RAM Mount

Mileage Trend:

I'll change plugs over the CRD problems.

Since buying this KJ back in '05, I've only seen 1 CRD here at the Jersey shore. Seems they weren't too popular around these parts, none of the Jeep dealers had any that I know of. I'm a big fan of diesel engines, and if there was one to be had, I probably would have purchased that over the 3.7 Lt gasser, but over all I gotta say I'm real happy with the power plant I have in my Renny, with the K&N on the intake side, the Thrush on the exhaust side, and these new Autolite double platinum's lighting up the mix, I've got plenty of power, and compared to the Dodge Ram 1500 4X4 I had before it that got 2 telephone poles to the gallon, the mileage on this Renny is quite acceptable.....

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2005 KJ Renegade
3.7 Lt. V-6
2.5" Daystar Lift
Thrush Welded Muffler
K&N (Poor Man's) cold air intake
Goodyear Duratrac 245/75-16