I am trying to sell some 4.56 gears that i had in my car when i bought it. They are richmond gears that were not used for very long. A guy on craigslist asked me what type of gears they were. He said they are obviously 4.56 gears for a 8.75 mopar rear end, but are they 489, 741 or 742. Just wondering exactly what this means and how to find out what they are...im guessing this means what rear end they are for but not positive. Just wondering if their is a easy way to figure this out. Thanks!
I don't think Richmond makes a gear set for the 741. The 4.56/4.57 part numbers for the 742 are 69-0047-1, for the 489 they are 69-0061-1. These numbers should be stamped on the ring gear.
741 has a 1 3/8" pinion stem, with carrier casting #1820657 or 2070741742 has a 1 3/4" pinion stem, with carrier casting #1634985 or 2070742 489 has a 1 7/8" tapered pinion stem, with carrier casting #2881488 or 2881489