8.3K is a long-long time using conventional inside an old, tired engine. That new oil may turn the dipstick black in the first few hundred miles.
The 20w50 should help slow consumption.
Out: Miles Lubricants Milesyn SB 5w30 (3,000 miles on oil) / Toyota OEM 90915-YZZF1 filter
In: 2QTS Miles Lubricants Milesyn SB 5w30 + 2QTS SuperTech High Mileage 5w30 / FRAM Extra Guard PH4386 filter