Anyone know what the correct mileage is for changing spark plugs?

 

According to my Jeep Manual - 99,000 (100,000) miles.

 

102,000 miles, 170,000 km or 102 months according to the 2010 owners manual.

 

Personally, I wouldn't wait that long. It a cheap investment to change them out sooner. You probably get a payback in slightly increased gas mileage as well.

 

Interesting that in 2007 they recommend 99,000 and in 2010 it's 102,000. Goes to show someone most likely complained that they were not truly 100,000 mile plugs so they had to make the adjustment! I have 42,000 on mine now and I am thinking I will change them out around 45k when I do my maintenance.....

 

I always change every 40-50k miles in any vehicle.

 

Thats when I plan on doing mine as well.

 

They're using platinum plugs (possibly iridium,) so going 100K miles is not a problem. You can change them early, but most of the time you're just throwing money out the window when you do. If you do change, make sure you buy a good quality plug that's the same or better than what's put in stock (i.e. no copper plugs, platinum or iridium only.)

These materials are much better conductors and much more resistant to wear than the old copper plugs were. The only real need to change them prematurely revolves around mechanical failures. Those should be resolved before worrying about the plugs themselves.

 

I changed mine out due to a sputtering problem. I changed mine around 35,000 miles. I have heard of many people finding out that their original plugs were not gapped correctly from the factory.

 

to change them at 102,000 miles.