Do I need to have them replaced now that I am at 107K Miles? I've read other threads of others on the forum that didn't replace til much later mileage.

 

Spark plugs "last" around 90K. If you haven't changed them yet, I would recommend doing it.

 

I would change it, I replace my plugs around 86k miles.

 

Probably not necessary. I've changed plugs twice now, each time at the 105K service interval (MID indicator "4"). The NGK iridium plugs are so good, the gap was still at factory specs each time. So based on my experience, you don't need to be in any hurry to change them this instant.

What about your timing belt? You should have received a "4" on the MID by now, unless that service has already been done....

 

They're so cheap you should. They're easy to DIY as well but make sure you have 3 inch extensions and spark plug socket and drop em in one by one.

 

When the daughter sold her Maxima at 264k miles, I had only replaced the plugs once at 131k miles, so the plugs had 133K miles and still going strong.
Don't recommend the extra mileage as never know when one will go south.