Does anyone know off hand the stock gear ratio in a 1964 98 4dr hardtop? Or if it’s stamped on the housing somewhere or in the vin code. Thanks for the help

 

Nothing in the vin. Should be a code stamped in the carrier. Don't know what the codes are for '64. I'm guessing it's a 3.23 or a 3.08. Starfires used 3.42s.

 

The diff carrier is stamped with a number on the outside flange where it bolts to the axle housing .
It will be in about the 7 o clock position as you look at it from the front.
The axle codes are listed in the 1964 Oldsmobile Shop Manual.
The letter "L" stamped next to the code number designates a limited slip (posi) differential.

 

Perfect. Thanks Charlie. I’ll climb under there and look.

 

Okay, so I have a 9. (3.23)

here is the chart for anyone that might need it in the future.

 

 

3.23 is my favorite ratio for these old cars. Obviously 3.08 gets better mileage, but 3.23 is more fun. Recommend against 2.93 if you come across it, best mileage, but not so hot off the line.

And we’re not keeping these cars for their legendary fuel economy, so why not have some fun?

 

Right, although I wouldn’t mind finding the 3.90L

 

It would leave two black marks on the road........

 

:d