Lifetime Gold Member
- Feb 9, 2008
If you look through all the pages of research I've done I've yet to find a 78 Z/28 automatic with the CHS code. CHS from my research is 100% a manual transmission code for the 78Z. I set out on this mission years ago to see for myself that the GM reference info that people have used for this site, and others, seems faulty in this regard.