Bologna

I would like to know what everyone would recommended for spark plugs for my 1997 Jeep Cherokee Sport SE 4.0L v6.

I haven't changed them since I bought it almost a year ago and my Jeep has 142k miles on it. I get roughly 16mpg and I think I should get better so I want to give it a little tune up. I figured I would start with the spark plugs. I read somewhere that if I replace the spark plugs I should replace the cap and rotor too? I'm definitely not a gear head so I would have no idea how to replace those. Any help would be appreciated.

Also I've always been told E3 spark plugs are the way to go. But I've read here that Champion cooper ones are better.

Thanks,
Kyle

Bustedknuckle

Champion Copper Part #RC12LYC

That plug was made for that motor.

Bologna

Thanks for the fast reply. Do you think this will help my mpg? Any other recommendations to help improve it?

EDIT: Is this the correct one that you recommend? (http://www.autozone.com/autozone/par...Number=RC12LYC)

Bustedknuckle

Buy a Prius.

Bologna

I can't, I love my Jeep and have too many long hours into it already. My pride wouldn't let me drive a prius.

Bustedknuckle

Right then, my next suggestion would be to try the search feature, located on the top tool bar, just to the right. Using this, you'll find every answer you ever did & didn't want to pretty much any question you'll ever have.

Best of luck changing the plugs on your V6.

tinytrax78

was 4.0 v6 a limited production motor?

Bologna

I'm aware of the search feature, but I wanted people's input on my specific Jeep. That and I found hundreds of different opinions when I used the search feature. It would have took you less time to answer the question than to type that.

Thanks for the part number on the spark plugs.

89Laredo

Maybe if you:
A: Cant read the emissions sticker. (you know, the BIG white sticker on the firewall?) Or the owners manual.
B: Cant tell the difference between an I6 and a V6
You should just pay someone to do it for you. Next thing you know well have another "HELP I STRIPPED OUT THE HEAD AHHHHHH!" thread.

I hope youve at least done an oilchange (or paid someone to do it) in the year youve owned the thing...

Bologna

I'm not sure, but my Jeep is a Sport Special Edition, so maybe that's why?

Bologna

My Jeep did not come with an owners manual.
My engine is an inline/straight six but I honestly never saw anyone say I6 before.
I've had maybe 4 oil changes since I bought it.

I just wanted to know people's opinions on spark plugs. I wanted to upgrade spark plugs, not only replaced them.

Bustedknuckle

Not trying to sound profound or come off like a douche, but there is nothing really "specific" about your motor. Over 17 years of production, quite a few were made, around 2.9 millon to ballpark it. Not to mention the same motor came in 2 generations of Wranglers, and 2 generations of Grand Cherokees. Just saying, these motors are basically everywhere. And information is quite common and easy to locate on them.

Tip: Running O.E.M (Original Equipment) standard parts will prove to be the best service parts and longest lasting parts you're vehicle will see.

And now for the usual with MPG's related threads, you're trying to hurl a shoebox down the freeway at 70mph, simple physics take over at that point. Aim for 19 mpg and call it a day.

Bologna

That's exactly why I posted this thread. I did not know that. But I knew if I did make a thread that I would get the most accurate information I needed. I didn't want to waste money on spark plugs that I assumed would work; I'd rather make sure they work before I buy them.

Bustedknuckle

It's okay, we can turn this ship around and get her pointed in the correct direction. We'll call this the official -

"Newb who signed up today to ask 1 question but wants to know exactly about his specific need thread instead of searching."

Thread.

So... deep breath... ready?





Also consider changing out your plug wires, as they have seen just as much wear and tear as the rest of the electrical system. Changing them out with a standard plug wire will be fine, either via Mopar from your local Dealer or Autolite seems to be a popular choice for O.E fitment (<- there's that word again!)

Next, as preventative maintenance, consider changing the distributor cap and rotor, seeing as they too have probably seen 142000 miles at this point. Also, given your exact climate, it might be a good notion to replace or at least purchase an ignition coil for spare or instant installation. Why? Because an ignition coil changes your 12v system to the required 150,000 to 170,000 volts required to achieve correct spark. It achieves this by simply spinning a copper wire around a magnet. But given the fact you absolutely love your XJ, I assume your already sold.

Other points of interest would include a fuel filter, air filter, transmission filter kit, flushing all fluids, i.e Coolant, transmission oil, front and rear gear oil, power steering fluid, brake fluid (D.O.T 3 or whatever you choose to supersede it). When changing differential fluid, be sure to add Mopar LSD additive, available at your local dealer for under $10 with tax.

Doing all that you will see another 100 trillion miles out of your beloved XJ.

Welcome to the cereal bowl, please stick around for the cookies and pie. We're a fun bunch.

Bologna

That's the post I was looking for lol. Thanks, 100 trillion miles sounds good to me