Still have the tag on the diff? Need more info. If the tag is gone from the differential it might have been changed. Could check the door tag as well
No tag on it. It's under my 53 chevy truck right now. I don't know really anything about it other than it is from a 67 Ranchero. Seemed like 1 wheel turn moved the drive shaft about 2.25. But that doesn't seem right to me.
For a non-posi, keep one wheel on the ground, then turn the other wheel exactly 2 tuns while counting driveshaft revolutions. Make chalk marks on tire and driveshaft to get it accurate. example: 3 turns exactly would be a 3.00 to 1
If you want to try a high tech approach to find out how far off your speedometer is get an onboard navigation system. It should tell you within a tenth of a m.p.h. how fast you are going. These things are super accurate. I’m guessing with the vehicle speed from the GPS unit, your engine rpm and your tire diameter you should be able to come up with a rear gear ratio. The old school way was to mark the tire and drive shaft with chalk and count the driveshaft revolutions, it sounds like you have already done this. Ford rearends usually have a metal tag on one of the carrier bolts, it will be stamped 3.00 or 3.25 ect. I have a '66 Ford Mustang, Falcon and Fairlane shop manual, they probably offered the same gears in the '67 Ranchero. They list a 2.80, 2.83, 3.00, 3.20, 3.25, 3.50 and 3.89:1 Jerry
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