Best performance chip and best spark plug??
Thread Starter
Newbie
Joined: Sep 2011
Posts: 6
Likes: 0
From: New Albany IN
Year: 2001
Model: Grand Cherokee
Engine: 4.7
What are the best spark plugs to buy for a 1996 Classic?
I want to increase my mileage
and performance chips? what is the best one to get?
Thanks!
I want to increase my mileage
and performance chips? what is the best one to get?
Thanks!
☠ CF Sheriff ☠

Joined: Nov 2009
Posts: 15,197
Likes: 18
From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
Performance chips do absolutely nothing on this engine.
As for plugs, any XJ below 1999 will run best on the factory Champion Copper plugs - RC12LYC, 0.035 Gap - good for your wallet too.
Bosch Plugs, especially the E3 ones do not do well in this engine
As for plugs, any XJ below 1999 will run best on the factory Champion Copper plugs - RC12LYC, 0.035 Gap - good for your wallet too.
Bosch Plugs, especially the E3 ones do not do well in this engine
Originally Posted by dukie564
Bosch Plugs, especially the E3 ones do not do well in this engine
CF Veteran
Joined: Jun 2009
Posts: 1,415
Likes: 1
From: Las Vegas, NV
Year: 1999
Model: Cherokee
Engine: 4.0L
Honestly for doing a tune up every 50k miles (and that's early)...extra cash for plugs really isn't a big deal. I put e3 plugs in my 99 Cherokee and it drives like a champ.
CF Veteran




Joined: Nov 2010
Posts: 5,840
Likes: 117
From: In the middle of Minnesota!
Year: 1999
Model: Cherokee
Engine: 4.0
Skip the chip and use Champion coppers for your 96 4.0 engine. Stay away from Bosch and E3 plugs; they will not help you, and in certain situations (not all) can actually misfire.
Be sure all tuneup parts are fresh. Plugs, wires, cap and rotor with brass contacts (not aluminum).
Use a bottle of quality fuel system cleaner every once in a great while to help optimize the spray patterns of the fuel injectors. BG44K and Techron are my favorites here.
Most xjs will get somewhere between 15-21 mpg, depending on engine efficiency, how you drive it, outside temperature, etc.
Last edited by tjwalker; Oct 14, 2011 at 06:26 AM.
Trending Topics
Member
Joined: Jun 2011
Posts: 172
Likes: 0
From: Santa Rosa Beach, Fl
Year: 2001
Model: Cherokee
Engine: 4.0
E3 are gimmicks. Put what the factory reccommends, champion coppers. Ive changed 3 sets of "expensive" plugs that havent lasted 20,000 miles before they started misfiring.
Newbie
Joined: Mar 2010
Posts: 22
Likes: 0
From: Greencastle, Indiana
Year: 1999
Model: Cherokee
Engine: 4.0
Dukie,
are the Champion RC12ECC ok to use too?
are the Champion RC12ECC ok to use too?
jbossnack,
I hope Dukie does not mind me answering for him. The best thing to do is to look under your hood and see what the sticker says to use. The sticker is above your brake booster. The RC12ECC are the correct plugs to use if you are running a 99 with an inline 6. The 2000's and up use an NGK Plug.
I hope Dukie does not mind me answering for him. The best thing to do is to look under your hood and see what the sticker says to use. The sticker is above your brake booster. The RC12ECC are the correct plugs to use if you are running a 99 with an inline 6. The 2000's and up use an NGK Plug.
Senior Member
Joined: Jan 2011
Posts: 689
Likes: 2
From: Upstate N.Y
Year: 2000.1999,1996
Model: Cherokee
Engine: 4.0
All xj run better with champion plugs not just 1999 and earlier,but NKG plugs work too.
I guess I was not understood well enough. Put what the sticker under your hood on the firewall above your brake booster says to run and you will be good to go. Unless you have a different motor in your vehicle than was installed in the factory. In such case, find out what the manufacturer of said engine recommends.



