- Sep 18, 2009
If I put my factory stock Pontiac 455 w/MY6 overdrive trans in my Bonnewagon might the 7.5" rear live? I know most would say "fugedaboutit". But I ran the same 7.5" behind a harsh Pontiac 400 for 10 years with no issues. I think it would help that I already have the same 3:23 guv-lock gears in it as I did then. The trans has a 3:1 first gear which adds up to 9.69 overall ratio. I feel 10 to one is ideal and this gets me almost that. Then the .75 overdrive reduces the 3:23 to 2:42 which is some nice highway gearing. And of course I am an "adult driver" and I don't do crazy clutch dumping anymore. What I am asking is would a 7.5" rear last during everyday normal driving? Someone on here posted long ago about running a 455 w/Saginaw trans and 7.5" rear. He said be nice to it and it will live. I would not want to search out an 8.5" rear if I don't absolutely have to.