My daughter has an 07 s80, 3.2 liter and is a royal pita to service and I dread every oil change. I’ve never done an analysis and really don’t want to, yet I get that’s the only way to tell how long she can go between changes. I’ve been doing 10-15k on liqui moly but have ran out and scored some crazy good deals on oil lately and wanted an opinion of which oil I should use and recommended length I can go. I’m not an extended drain kind of guy but being a non turbo with a huge sump I feel you can. The car takes over 8 quarts and uses a canister filter, which I use Mann filters. On hand I have these oils. PP 5-30 HM Valvoline 0-40, not the European oil PP 10-30 Mobil 10-30 HM synthetic The car uses no oil and no drips or leaks and has just over 100k.
In our volvos I've leaned towards the heavier - 10-30 and 0-40 oils. The OM on ours listed 40 weight as acceptable, and they stayed quieter on heavier oils when running the 7-10k OCIs we do in my home. Our S60s have 10 bolts I think for the splash guard and I usually drive them up on a couple of stacked 2x10s for a little wrench room. Yes, they take a little more time, as they have no ground clearance.
We do have a mityvac - and if your circumstances don't favor taking off the engine diaper, it's a no-fuss, almost relaxing way to go. Well worth the money, especially if you choose to change things like steering fluid and transmission fluid. I wore my first one out, gave it to a friend (they sell rebuild kits for them) and bought a second. Remember that these cars have a complex breather system that *will* punish you if you do not stay on top of oil changes and use a full syn oil.
I had an s60 t5 for years and was one of the best cars I’ve ever owned. I believe the manufacture recommendation is 7500 which I always followed with a 6qt capacity. The 3.2 is non turbo and from what I’ve read on Volvo forums is rather easy on oil. My t5 oil was black as night when I drained as the 3.2 is still very clean at 10k. I know color means very little but clean oil gives me a warm and fuzzy as opposed to to the color of tar. Is valvoline or PP considered extended drain oils?