905

German servicing information manual for launch of 1968 911 and 912 model years, with 22 pages of Sportomatic technical information.

Often difficult to engage 1st gear
Adjust the shift coupler as on manual car. Replace worn bushings if necessary.

‘Grabbing’ shifting from neutral/rough shifting
This is often the result of a poorly adjusted vacuum switch, which is attached to the intake manifold. An adjustment screw hardens and softens the clutch take-up.

The car becomes stuck in gear after being engaged for a few minutes

Produced from 1968 to around sometime in 1980, the Sportomatic transmission was based on two gearbox models, Type 905 and 925. Unlike a conventional automatic transmission, the system can be described as a 'clutchless manual' gearbox.

Anyone who knows more please comment, and I'll make a cohesive article out of it.

• Based on 905 manual
• Maximum torque application at stall: 2.2
• 7:27 pinion and crown wheel in place of 7:31 compared to manual
• Max input torque 127 lb/ft - at some time was upgraded to 141lb/ft (WHEN?) when the housing was upgraded to die-cast aluminum.

Differences between 906/00, 905/00, 905/01, 905/13, 905/20, 905/21?