Thanks so much. I could find the definitions, but it was so different from my darts rear I was lost. What designates the clone or clutch? Or do I just need to tear it apart? It's either an open diff or broken.
If original it would be a clutch type Sure Grip unit known as a Dana power lock I believe. The cone type Sure Grip did not come into heavy use until 1969 or thereabouts
If you read post number two you will see that the 1 3/8 and the 1 and 3/4 and the 1 7/8 we're all use from 57 up. They just had different numbers for the housings.
