Does anyone know when Ford went from a 8" to the 9" rear end. This info will help me in my search for a new carrier and ring and pinion.

 

They used them at the same time - just different applications. 9" started in '57 and were used thru the 80's.
I have an 8" in a '70 Stang, but I'm not sure of the time span for them.

 

The 8" came out in 1960 in the Falcons and continued up into 1977 in the Maverick. After that it was the 8.7 rear end ( crap). The 8" was used in Mustangs, Comets, Fairlanes, Cougars. Like the 9", it was a tough unit, but not as popular, and not made for H/D hot rodding.

Barry