I would be using a thicker oil such as the 15W50 in such a hot climate.
The 95 E320 wagon doesn't use any oil, none and it has 98k
The 91 300E has 215k and uses about a quart every 2,500
The 190e has 213k and use 1 quart every 5k miles.
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)