Good discussion here. I am on the 'follow the factory guidelines' path in general. I'd like to get an opinion and I am also going to run this by the dealership. I bought a 2017 S90 T5 Momentum used. The vehicle had 11,300 miles on it when I purchased it. The original owner had the 10K service performed at 7500 miles by a local dealership here in Raleigh, NC. I have a copy of the service order because it was in the dash at purchase. The car now has 17,500 miles on it and the service indicator light is on (as expected). I'd love to get back onto the '10K/20K/30K' schedule so I am thinking about letting this run until 18,500 miles, then adding another 1000 miles at the 28,500 interval (doing the work at 29,500) then getting back onto the normal demarcations at 40K.
Like @stick_shift, I plan on having UOA performed and I also use Blackstone labs for UOA on my 2016 GMC Canyon (Duramax Diesel engine). Not because I feel that I 'have to' but more for my own curiosity! BTW @stick_shift - my Canyon had exactly what they talk about with new vehicles showing up higher than normal metal content due to break in wear. It settled out for oil changes 2 & 3 and now after #4 is pretty low. Interval on the Canyon is calculated via driver info computer (% Oil Life) but in general is 7500 miles or so for the way I drive it.
So - the question here is, "How 'risky' is it, if at all, to slightly extend the service interval (adding another 10% to it)?" I am confident that Volvo has some variability built in, but not sure how much. Plus there is an issue re: extended warranty (I have a 6 year, 100K mile Volvo VIP Platinum Warranty) that requires service 'according to manufacturer recommended intervals'. All this being said, I am pretty comfortable with tacking another 900 - 1000 miles onto the window, but wondering what you guys (and girls?) thoughts may be in this area?