Hi Jennifer, a relatively easy way to tell is to put the car on a lift or jack stands and remove the lower cover plate for the transmission (I assume you have the aluminum torqueflite). Put a dab of paint or marker on one tooth and rotate the flywheel using a tool and the ring gear teeth, counting teeth until you come back around to the marked tooth. Even if you lose count by one or two, you should be able to tell the difference between 130 teeth and 172 teeth. They make a tool to rotate the engine in this manner, but I have always good luck with a large flat bladed screwdriver prying against the bottom of the engine block. A little tape on the screwdriver preserves the engine paint. Hope this helps. Bill Huff 600-3041 Flywheel gear, AT or MT, 130 teeth, 12.16" diameter 600-3016 Flywheel gear, AT or MT, 172 teeth, 13.56" diameter It seems as though I may need to replace the flywheel gear on our 1962. The listings above are on the club website as NAPA parts available for 1962. Anyone know which of the two listed I would need? Or do I need to pull the flywheel first and measure it? Were they all the same for the 300, Newport and/or New Yorker? Or is it a 383 vs. 413 thing? Thanks! ure [Non-text portions of this message have been removed]