gear ratio 1972 model 4 door sadan
There were a number of optional gear ratios available. Your VIN should decode this, or the build plate on either the door, trunk lid, or fender well. GM uses what's called a Service Parts Index sticker which has numbers on for the various options installed on the vehicle. Another option is to get underneath and look for a metal tag bolted to the differential, which should tell gear ratio.
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