Mercedes-Benz 2009 GL320 BlueTEC Operator's Manual page 428

Technical data
Rims and tires
Same size tires
Model GL 450
Rims (light alloy) 8.5 J x 19 H2
Wheel offset 2.20 in (56 mm)
23
All-season tires 275/55 R19 111H M+S
23,25 265/55 R19 109H M+S.
Winter tires
23,25
All-terrain tires 275/55 R19 111H M+S
Rims (light alloy) 8.5 J x 20 H2
Wheel offset 2.20 in (56 mm)
Summer tires 23
275/50 R20 109W
23 —
All season tires
23 Radial-ply tires
24 Must not be used with snow chains.
25 Not available as factory equipment.
26 Standard tire without run-flat characteristics. Equipping vehicle with TIREFIT is strongly recommended.
27 Must be used in conjunction with Tire Pressure Monitoring System (U.S. vehicles) or Run Flat Indicator (Canada vehicles) only.
426
24
24
24
GL 320 BlueTEC
8.5 J x 19 H2
2.20 in (56 mm)
—
26
265/55 R19 109H M+S.
24,26
275/55 R19 111H M+S
8.5 J x 20 H2
2.20 in (56 mm)
—
275/50 R20 109H M+S MOExtended
24,27