I concur with the rest of the guys here. Boy, your TBN sure got beat up…hard city driving. You can see this in your Silicon reading too; lots of dust/dirt.

Just so you have a point of reference, I have a S70 T5 (high-pressure turbo), live in Fresno (hot/dirty summers). I run Amsoil 10W-30 (ATM) and the Volvo/Mann cartridge-type filter. I change the filter every 6 months (about 4-5K miles), top up, and run the oil for 1 year (around 10K miles). Based on oil analysis experience, my oil, even in my turbo, can easily go 10K miles under hot, stop and go driving.

Understanding your climate, I would run the Amsoil filter with their 10W-30 (ATM) oil. Change the filter at 6 months (or earlier if your mileage exceeds 12,500 miles) then change at a yearly interval. I’ve been doing this on my Jeep Grand Cherokee for the last 4 years/approx 90K miles with zero problems and zero oil consumption. In my Volvo, I run the oil for about 8 months and change it based on mileage. It burns about ¼ quart of oil in between filter changes. This is very low and acceptable for a turbo.
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1999 S70 T5