Speedometer Angle Drive Problems

[jpavone@vanstar.com]

I have had problems with the output shaft  in a brand new right angle drive
twisting off. This has happened 3 times. The speedometer has also been
rebuilt, the cable is new and has no kinks . The cable inserted in the
speedometer turns smoothly by hand in either direction. Everything works
fine for about 30 miles and then the drive fails. The transmission is a
freshly rebuilt  Cortina 4 speed. Any help would be appreciated.

Regards,

John