Here's my two cents on this one. There's actually nothing wrong with used gears as long as the bearing diameters aren't scored, and the wear pattern is good. just make sure they are a set. (not a ring out of one set and a pinion out of another set, even if they are the same ratio as they wear together)I've had a couple Mustangs with 9" rears and I also used to mud drag a '78 Bronco with a 9" rear, so I usually had a few sets of gears in different ratios laying around. Put lots of gears in different vehicles and never had a problem.
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1985 Mustang GT
'85 GT 13.20 @ 105.8 / '72 Mach1
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