- 206
- 14
- 28
- Location
- Brenham, TX
The speedometer cable adapter on my M521A1 (MACK) seems to be the cause of the speedometer not working. The -20P parts manual calls out two different adapters. A regular one and one with a drive ration of 26 to 1. Does anyone know which one I would need? (transmission is an overdrive transmission).