Porsche 911 Turbo 2007–2009 — technical service bulletin
Bulletin No. 85-21 · NHTSA communication 10203025 · issued Oct 15, 2021
Technical service bulletin
communication type
Wheels
component
2007–2009
model years
4
vehicle entries
Official summary
Instructions on the manufacturer's certificate for approved winter tires, wheels, and snow chains.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.