who makes the best spark plug? - Page 2 - JeepForum.com
LinkBack Thread Tools
post #16 of 49 Old 05-05-2009, 12:36 AM
Registered User
1976 CJ7 
Join Date: Sep 2008
Location: Greenville
Posts: 1,102
I like NGK's. Every NGK plug I've ever pulled from the box was correctly gapped. Definitely can't say that about Champions. However, they are sometimes difficult to find for American trucks. In these cases, I use Autolites.

I definitely wouldn't waste any money on platinum plugs unless the manufacturer calls for them.

jumbojeepman is offline  
Sponsored Links
post #17 of 49 Old 05-05-2009, 07:35 AM
Happy Joe
Registered User
2006 TJ Wrangler 
Join Date: Jun 2007
Location: Colorado, USA
Posts: 2,396
I use champions, with a brass terminal distributor cap (aluminum terminals are a hidden problem waiting to happen) along with a msd-6a ignition box. Check and re-gap the plugs every 75,000 miles or so.


'06 TJ Rubicon; seemed like a good idea at the time; had many CJs...
Happy Joe is offline  
post #18 of 49 Old 05-05-2009, 07:06 PM
Registered User
1996 XJ Cherokee 
Join Date: Jul 2008
Location: Maine
Posts: 1,754
Good 'ole (and cheap) Champion Copper Cores are in my Jeep. Runs great!

-Max Black 1996 XJ
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

4.5" lift of assorted brands, 33x10.5 KM2s on D-Windows, JCR rear bumper, Nates Slimline w/Champion 8k winch, custom half doors, roof rack, and tire carrier, Maine Woods dents and pin striping, and various other cool things.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Maine Jeep Club Member #1 Firefighter Jeep Club Member Black Jeep Society Member #163Survivalist Jeep Club Member #14
1996BlackXJ is offline  
post #19 of 49 Old 05-07-2009, 10:44 AM
Registered User
1999 TJ Wrangler 
Join Date: Dec 2007
Location: Ontario, Canada
Posts: 2,765
Anything but Bosch

The +4's are too cold of a plug in the 4.0L and they will carbon up.

My Thread with pics from trying Bosch +4s http://www.jeepforum.com/forum/f9/spark-plugs-should-have-listened-jerry-541430/

I now use Autolite AP985's and they work great . If you have a distributerless ignition use the APP985s (Double Platinum)

Friends don't let Friends run Bosch
Pillswoj is offline  
post #20 of 49 Old 05-11-2009, 10:19 PM
Registered User
1995 YJ Wrangler 
Join Date: Jul 2004
Location: Indiana
Posts: 1,849
I tried to run Bosch in my 89 4.2. It missed and sputtered so bad I went back and bought Champions the next day. Problem solved. I will never run another Bosch plug.
1998zj is offline  
post #21 of 49 Old 05-12-2009, 03:27 PM
Registered User
1982 CJ5 
Join Date: Jun 2006
Location: Yakima, WA
Posts: 1,200
I'm throwing in my vote for Champion truck plugs too. I've tried everything from them to the most expensive 4 tip platinum plugs you can buy and I've always gone back to Champion's. I threw a set of Bosch Platinums in the garbage the day I bought them because my Jeep wouldn't run worth a crap. The Champions just seem to run so much better in my motor, never had one problem.

1982 CJ-5 Laredo 258, T-176, D-300
1972 240z in pieces...

Originally Posted by BESRK
...that's why you push in that little nipple (hehe.. I said nipple on the internet :D )
KrazyGimp is offline  
post #22 of 49 Old 05-13-2009, 09:00 AM
CoriolisSTORM's Avatar
2010 JK Wrangler 
Join Date: May 2004
Location: ???
Posts: 1,224
Bosch +4s go in my Caliber. My wrangler 2.5L only gets Champion truck plugs. Only replaced the plugs once in it, and neves done the rotor/cap in 80k miles and mine still runs great.

1998 TJ Wrangler SE - Stone White, 2.5Ls of screaming lifter clacking power, AX5, 31" BFGoodrich All Terrain T/A KOs

2010 Wrangler Unlimited Sahara - Deep Water Blue, 3.8Ls of oil consuming fury, NSG-370, BFGoodrich Rugged Terrain T/A 265/70/R18s
CoriolisSTORM is offline  
post #23 of 49 Old 05-20-2009, 12:49 AM
Registered User
1990 YJ Wrangler 
Join Date: May 2009
Location: Tampa, Florida
Posts: 27
I used to own a saturn and am a member of a forum for saturn enthusiasts (let the flaming begin, i know...). Everyone over there hated bosch platinums like the plague. Equated in usefulness to the turbonator. NGKs seemed to work well for my N/A 4-banger that I had.

'90 YJ 6cyl \______/
AndThenRobSaid is offline  
post #24 of 49 Old 07-03-2009, 09:57 PM
Registered User
2009 JK Wrangler 
Join Date: May 2009
Location: Temecula
Posts: 165
My '09 JK comes stock with platinum plugs (according to the manual), but since I am installing a RIPP Modifications Supercharger, their kit comes with NGK IX Iridium plugs one step colder than stock. I was looking for better spark plug wires and decided to purchase the MPG Plus Spark Plug Wires by Granatelli for the JK. They are "0" resistance wires and suppose to deliver more spark to the plugs. I have a concern that the coil may prematurely fail due to the zero resistance and need a lead on a high performace coil to replace the stock one. Can't seem to google one on the internet????

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
TDmaster is offline  
post #25 of 49 Old 07-03-2009, 11:02 PM
Registered User
2001 TJ Wrangler 
Join Date: May 2009
Location: Greenville, NC
Posts: 181
I know the newer (01+ maybe) 4.0's have coil on plug. It wouldn't surprise me if the V6's in the JK's did too, but I have no idea. You've done your research/know what you're talking about, right? I only say that 'cause I know someone that went to buy plugs/wires/coil for his TJ, only to find out that he didn't have them . That really threw him for a loop.

Drew, KJ4MUZ
cntp is offline  
post #26 of 49 Old 07-04-2009, 12:52 AM
Registered User
2010 JK Wrangler 
Join Date: Jun 2009
Location: Planet Earth
Posts: 171
I've used Denso Iridium plugs in a SC 3.2 MB motor and noticed a fairly substantial difference. If they make them for the Wrangler, i'll throw them on when the time comes. I also changed the stocke wires to Magnecor 8.5mm - --pretty nice.

"It is the spirit of men who follow and of the man who leads that gains the victory" ~ George S. Patton
RRCP08JK is offline  
post #27 of 49 Old 07-11-2009, 08:51 PM
Registered User
1996 ZJ 
Join Date: Feb 2009
Location: Surgoinsville, tn
Posts: 168
i use autolite 24s and they work great

96 zj. 31x10.50 uniroyal awts. 2.25 bb rough country 9000 shocks. rustys transmission crossmember
cobra radar detector future mods:rustys 5.5 long arm kit and smittybilt xrc8

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
southernmudzj is offline  
post #28 of 49 Old 07-11-2009, 11:06 PM
Registered User
2012 WK 
Join Date: Sep 2008
Location: Burlington, Kentucky
Posts: 5,533
More electrodes Does nothing those +4's worthless they all take path of least resistance so if 1 plug was off .0000000000000000000000000000001 that is the side that gets the spark.

I use autolights in the 4.0slow

Sold4" Hybrid lift TeraFlex coils IRO Adjustable LA's Jks tracbar 1.25spidertrax spacers 265/75/16 Dura-tracs
Originally Posted by moPowered View Post
The SRt-8's are a liberty design.
2011 WK2 ORA2 sold
2012 WK2 SRT8 - Current
99 WJ Limited Lifted.
2001 WJ stock 4.0 304k miles
xJoshxx is offline  
post #29 of 49 Old 07-15-2009, 11:18 AM
Registered User
2002 KJ Liberty 
Join Date: Jul 2009
Location: Alexandria
Posts: 335
Libertys might not be the most popular jeep for trail riding because of the IFS, but I try anyway...

That said, I need to replace my spark plugs and I was looking for the best spark plugs I can get. Whatever came with my jeep are still in there at 55k and I am starting to feel the engine not running as smooth as it used to.

I read through the thread and you guys seem to like Champion... but should I go with Platinum or Iridium? There is a $6, Iridiums being more expensive. Thoughts?

Any other tips would be appreciated, I want to get the job done well and right the first time.

Edit: Also, I am getting many mixed results as to the gapping for my vehicle? The spark plugs say do 0.035, under the hood says 0.040, and haynes manual says 0.045? What gives? Who should I listen to?

Last edited by brendanc; 07-15-2009 at 12:26 PM.
brendanc is offline  
post #30 of 49 Old 07-15-2009, 11:31 PM
Web Wheeler
2006 LJ Wrangler 
Join Date: Apr 2007
Posts: 3,849
I don't know what is best for a 2.5L or a 4.2L, but I know from experience with my XJ and LJ that the 4L loves NGK copper plugs. Just the regular NGK copper, not the platinum.

I once tried some fancy Bosch platinum 4 prong plugs in my XJ and it ran terrible (no low end torque). The stock plugs (Autolite I think?) are OK. Boche terrible. NGK cooper are by far the best for the 4L (idles smoother, same midend and highend torque as the other two plugs I mentioned, but way better low end torque and smoother running at lowend).

For the 4L I've found NGK are the best. The regular cooper NGK.

NGK also worked best in my motorcyle. I'm really an NGK fan after trying Champion, Autolite, Bosch, and NGK in various engines.
CB3 is offline  

Quick Reply

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
4.0L Spark Plug Dilemma gmcd Engines & Drivetrain 7 08-12-2009 08:14 PM
Spark Plug Question GADawgFan Engines & Drivetrain 2 06-10-2008 06:28 PM
Spark Plug Boots Jerry All-Bran Engines & Drivetrain 5 04-15-2006 09:38 AM
spark plug change 01jeepgrand Audio, CB & Ham Radios, GPS, & Electrical 3 08-22-2005 06:46 PM
spark plug gap badams Engines & Drivetrain 5 07-20-2002 07:59 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome