2001 Spark Plugs

I am planning on putting new spark plugs in this weekend and was curious if these are good for the 2001 XJ... NGK V-Power..part# ZFR-5N. Any suggestions or tips about this job would be very helpful.

So, I bought this 2001 XJ a couple months ago and so far this is what I have found / done:

1. New Radiator - the fluid had never been changed in 110K and ruined it. (FIXED)
2. New Tires - the tires that came on it were terribly bald. (FIXED)
3. Brakes - took it in and the rear brakes have never been serviced... Is that normal? I will replace all brake parts next month, rotors, drums, pads, springs...
4. Rear Lift - the rear was sagging considerably, I just installed a leaf helper lift and it worked fine. Added about 1.5" to the back. (FIXED)
5. Air Filter - was black and looked like factory, installed a K&N (FIXED)
6. Dash Lights - some of the lights are burned out. I am waiting for the LED's to come in and then will replace.
7. Suspension - Havn't had it checked out yet but assuming that it needs to be looked at.

It looks like it was really neglected before I got it but want to breath life back into it. Any ideas of stuff to look at would be great!

I love my NGKs FWIW.

those are actually the recommended plug for later model 4.0's, so you're good to go

If it was that neglected, I would change:

Engine oil
Transmission oil and filter
Front and rear diff oil
Brake fluid

Change the fluids. You know about oil (watch the ZDDP for the flat lifters), but also change the transmission fluid, front & rear end lube, transfer case lube, power steering fluid and brake fluid. This will save you money in replacement parts and increase your reliability.

Put a little dielectric grease around the top porcelain where it mates with the coil boots. Try to keep it off the electrical contact areas. I guess anti-seize is good on the spark plug threads, but is optional for our cast iron heads.

Check the play and toe in of your front steering.

Good ideas thanks guys. This truck limped to my house when I got it. Looking better now:

Posted in OEM and Modified.


Change the fluids. You know about oil (watch the ZDDP for the flat lifters), but also change the transmission fluid, front & rear end lube, transfer case lube, power steering fluid and brake fluid. This will save you money in replacement parts and increase your reliability.

Put a little dielectric grease around the top porcelain where it mates with the coil boots. Try to keep it off the electrical contact areas. I guess anti-seize is good on the spark plug threads, but is optional for our cast iron heads.

Check the play and toe in of your front steering.