Greeting, I'm looking for a good usable 57 olds drop out unit for 29 spline axles. Would like to get 3:36 or a little lower. Posi would be great not necessary
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3.64 is about as low as I recall coming from the factory. 57-58 are the same, except......"anti-spin" (Positraction) came out in 1958. Fabcraft Metalworks did have a selection of new ring and pinions available. Check with them to see whats available.
Phone: (800) 208-8242
https://www.ebay.com/str/fabcraftmetalworks

Jim @ JD Race.com is my preference. Phone: (330) 990-8155
http://www.jdrace.com/

 

I've got some 1957-64 rear end parts. But I don't know for sure what years/models they are from. If you could help key it out I might have something that would work for you. The weight for shipping might be spendy though. What part of the country or countries are you in?