Subject: Transmission Mainshaft Nut Models: 911 1972
Bulletin Number: 84 – 02

The torque specification for the castellated nut on the mainshaft (M18 x 1.5) has been increased to do 160 Nm (118 ft lb).
This increase has been in effect in production as of January 24, 1984;
VIN 91 ES 121121
91 ES 161110
91 ES 170632
During repairs on older transmissions, built as of the 1972 Model Year, torque the nut to the new 160 Nm specification.
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