Hi Guys I finally got around to check to see what gear rearend I got.
first one is CITT-T 5443-2 7-62 5.13 This is the one in my 66 F350
second one is CSTA-TA 2722-1 4.88 This the spare one I picked up.My question is what style rearend is it.And is the second one any better gear then the first one?Tring to find one that will beable to take the truck on the interstate.Thanks Tony

 

C5TA-TA = Spicer 70 = 4.88-1 = 7.4M

C1TT-T = Spicer 70 = 5.13-1 = 7.2M

In the 70 Series from this time frame, the "High Speed" rear axle was a 4.10-1. The next was a 4.56-1.

Both rear ends use the same parts lists numbers (96) in the parts books.

C1TT-T is not listed in the 1964/72 truck parts book, only in the 1957/63 parts book (prolly swapped into your truck yrs ago).

The C5TA-TA is shown in the 1964/72 parts book.

 

higher the number the lower the gear ratio, if you want highway gear you need a 3.55 or 4.10. call me tony