Quote:
Originally Posted by JerzyIroc
you can then get thicker gears for use w/ a 2 series carrier.
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http://www.jegs.com/p/Richmond+Gear/...10002/-1/10167
Check out the
10-Bolt 7.5'' & 7.625'' section. You will note that they list gearsets for both 2 and 3 series carriers.
Back when they only made one type of gear set for each rear type (regardless of carrier) you had to use a spacer to use the 3-series gears on a 2-series carrier. Using spacers is not really a good idea so Richmond and some others decided to manufacture their gears "thicker"- or, in other words, "build the spacer right into the gears" so that you don't have to use one.
The reason for this extra "space" that needs to be taken up is because of the thickness of the ring gear flange on the carrier. Lower numerical gearsets have more teeth on the pinion gear so it's larger, and the ring gear has to move out to make up for this extra size. On 2 series carriers the flange is thinner to allow for this. Higher numerical gearsets have a smaller pinion so the ring gear has to be closer to the pinion, and the flange is thicker. The difference between the flanges is how big the spacer or extra material on the ring gear is.