Due at 70k miles:
http://volvornt.harte-hanks.com/manuals/2013/2013-Volvo-Maintenance-Schedule.pdf

No reason to think that's not the right number.

 

I used Bosche double-iridium spark plugs during my 60k service. They are like a dollar more than the others (copper, platinum) and have a 100k mile warranty. See http://RockAuto.com

 

My coworker has a 2003 Tahoe with 340,000 miles. He tows his boat with it. It has the original plugs. His wrench pulls a few out and says they are good. MPG is the same as new.

Should we tell him his motor is going to wear out prematurely if he doesn't change his plugs?

 

I changed out the original Denso iridium plugs from a Honda 3.5 with 120,000 miles on them, and they looked ok. I didn't notice any changes at all with new Denso iridium plugs. So, I'd say they were probably good for a bit longer. Would I push them to 340,000 miles? Um... no.

 

I don't know what to make of that 340k mile story. Never change the plugs? Am I right in saying bad plugs can wear out the coil packs and presumably also other ignition system related items? I've heard tales of people recycling the engine oil from one car and using it in their beater car and that apparently works fine too but I don't see why you'd cheap out on basic maintenance.

 

"My Grandmother smoked since she was 8 and lived to be 95, so I'd say smoking is perfectly healthy." - You guys, probably.

 

Prior to 2013, interval is 52.5k miles for 2.5T and T6 cylinder engines, 75K miles for V8 and I6 engines.

After 2013, looks like Volvo rounds the 75k down to 70k miles, by then the only engine being offered in the US for the XC90 is the I6.

Can see maintenance schedule for your car here: \http://volvo.custhelp.com/app/homeV3

 

If they're copper plugs I'm not surprised by the interval, as that's normal... But I can't find anything that says what they are, and I'm a bit surprised to see a premium car made in 2013 equipped with copper plugs.

 

Plug life is strictly a function of what type of gas you burn (not grade of gas, but brand of gas and the additives) ... and time.

Manufacturer recommended plug interval is based on their assumptions about the quality of US gasoline.

This can vary greatly because of the way gasoline is distributed throughout the country. In the US we use "jobbers". They are the ones who blend the ethanol and additives package into the refined fuel purchased from the refinery. What you end up purchasing at your favorite gas station is a big mystery (brand name and advertising notwithstanding...)

 

if there not that bad just take them out and clean the carbon off them

 

My 2004 S60 2.5T went 107,000 when I took it in for an intermittent misfire. They replaced the plugs but probably could have just cleaned them. The coils were 12 years old and went 130,000 before a misfire..... I decided what the heck and replaced the timing belt at the same time.... YMMV

 

My thoughts on spark plug intervals...

- Copper: 30K-35K
- Platinum: 70K-80K
- Iridium: 80K-100K