The R10Q OD was available from 66 through 69. Some may have been available in 1970.

Most stock applications used a 4.10:1 differential ratio when the OD was ordered. My 56 has a 3.90:1 rear end and it works well.


Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine