60,000 miles.
It is moderately easy to change the spark plugs on a Liberty, although it is rather tricky because of the gap between the spark plugs.
They should not need changing until 90,000 miles.
Change the plugs at 100,000 miles or earlier if the engine is not performing as it should.
What distributes power to spark plugs on 2002 jeep liberty
Use what ever Jeep built it with.
On the right side or the left side of the head.
According to the owners manual, they have platinum plugs that should be changed at 100,000 miles.
If they are platinum plugs, should be every 95,000 to 100,000 miles.
If using standard copper core spark plugs, every 30,000 miles. If using platinum plugs, up to every 100,000.
when do you change spark plugs
30,000 miles is recommended for spark plug replacement on all Chrysler/Jeep vehicles, not just the Jeep Liberty. Not only are plugs recommended at 30,000 miles, shock absorbers are recommended as well. As a mechanic for the Chrysler/Jeep Corp., i can say with confidence that it is not entirely necessary to change plugs and shocks at the 30k mile mark. Basically, "If it ain't broke, don't fix it!" (however, i do recommend at least checking the plugs at 30,000 miles)
Change the plugs and wires at 100,000 miles unless you experience poor performance or a drop in MPG. In that case change them sooner.