Mopar Action On-line – Tech Questions
Darryl Pyle, Dunnville, 1970, dodge, charger, 318
Will 2.45 and 3.21 interchange in an 8.25 b body rear?
In a word: yes. Any ratio will fit the housing fine. But the 2.45:1 gearsetrequires a different differential case than 2.76 and up. You didn’t saywhich way you’re swapping, but either way, the diff, Sure Grip or not, willhave to change. This is because the 2.45 gears, if they had been designedfor the standard differential, would have been so thin that there would havebeen no room for the attatching bolts – and crazy glue isn’t very good atholding ring gears in place.
By the way, the even-more-insane 2.26 gearset used the same diff as the2.45s.