Buy OEM 1991 Porsche Part # 311601361 (281601361, 311-601-361, 95536107100). Tire Valve Stem. Tire - Repair or Replace Some signs that the tires on your 1991 Porsche are in need of replacement include

Valve. Stem. Rubber.
Tire Valve Stem. VAL. Fill. Tire.

Tire Valve Stem

Fits 911, 928, 968, Boxster, Cayenne, Cayman, Panamera, Taycan

Tire - Repair or Replace
Some signs that the tires on your 1991 Porsche are in need of replacement include tread that is worn to the treadwear indicators, tread that has worn unevenly, bubbles or tears on the sidewall, and a scalloping wear pattern—this can result in a steering wheel shimmy at high speeds.