Klaus,
You piqued my curiosity. What are "green rings that only last 50-75K miles"? Watching old consumption is a bit of a bother. Volvo, like a similar brands has eliminated the tradition oil dip stick. Now, you have to turn the car on to power the computer tablet located in the center of the dashboard. You have to touch the "Engine" icon and then scroll down to check the oil level. They you see a oil bar format, similar to what you would see on traditional dipstick. There is an illuminated needle between the "Low" and "High" points on the screen that indicates the oil level. I do check it, but not as frequently as I would if it was a traditional dipstick.

I wish Volvo still equipped its cars with traditional oil dip sticks and conventional spare tires. My XC90T8 does not have a spare tire. Instead it is equipped with a air compressor to which you install a can of sealant. The air compressor shoots the sealant into the tire and plugs it temporarily so you can drive the car to a garage. Later, you have to replace the tire, replaced the air hose from the compressor and have the Volvo dealership use a special tool to removed the discharged can of sealant to install a replacement. I can only imagine how much it costs to have the air compressor serviced after using it to fix a flat. Oh, by the way, if the hole is in the side of the tire, you are stuck. The sealant will not work and you will be compelled to have the car towed to a garage. To avoid this scenario, when ever I take the car on a long distance trip, I put a Volvo donut tire I purchased separately. The spare tire rolls around in the back of my car like a dead body. Not very sophisticated but it does give peace of mind. I suggested to corporate Volvo they should sell a retrofitted convention spare tire in place of the air compressor. Unfortunately, my suggestion has fallen on deaf ears.

Klaus, Merry Christmas and Happy New Year. Thank you for sharing your knowledge and insights.

Hugh