SlowGS3

I have a 95 GS300 with 118K miles. I bought the car at 110K and switch to mobil 1 synthetic at 114K and I have added almost 2 qts of oil and I have no clue where did it go
car don't have any blue smoke (or smoking at all) so I assumed it did not burned oil. It does have some minor oil leak but not a single drop on the ground when park over night. where else can the oil go??? I plan to switch back to dino oil soon and see how it goes.

Lexmex

I had this problem when I was using Mobil 1 5W-30 for a bit of time, even a gas analysis (like emissions) showed it was not burning oil but it was definitely dropping. I switched to a 0W-40/5W-50 blend of Mobil 1 and no problems since. I have 96K on my RX. I also checked for leaks both at home and at the office, but nothing underneath, no matter if hot or cold and I checked several seals.

SlowGS3

I currently using 10W-30, I may try 10W-40 but they don't have it in the 5 gallons jug

Lexmex

You can't win in some places.

Some of my racer friends use Liqui-Moly 10W-60 given issues with 10W-30, especially my friend with an RX-7. Not that I would use Liqui-Moly for my oil, but going to the higher weight helped.