BoostedBeaver
Moderator
- 951
- 265
- Aug 15, 2009
-
Augusta,
Georgia
I have been shopping for a four bolt, and will be picking it up Saturday. I do trust the gentleman that I am picking it up from, but I must check the rear myself. I am wondering the means and ways of identifying the difference from the auto 4 bolt rears to the manual rears. Also a quick way to determine 1g or 2g. Here is what I have come up with so far.
1G cars have cups that are held to the axles by bolts.
2G cars have a rear axle that is held in by a nut. The axle slides into the diff, the wheel side of the axle is slid through the knuckle assembly and held in by a nut. This is much like the front axle design.
1g 90-91 rear service info.
2g 97-99 rear service info.
One sure fire way to check the rear is to count the ring and pinion gear teeth. By doing this you will verify and have no doubt of what rear you are getting. You can see above that all years (90-99) use the same gear reduction type. All manuals use a 3.545 reduction ratio while all automatics use a 3.307 reduction ratio. Drive gear teeth and pinion gear teeth vary based on AT or MT and viscous LSD or conventional diff. Use the chart above to find out what diff is in front of you.
I do not know any of the codes on the rear diff covers. I know that the combination on the rear diff cover is not a sure fire way to check the diff, but it would be a good fast check. If you know the codes (B1G, B1H, B1J) and which vehicle they belong to, that would be great. Any additional info would be great. Hope this information helps others and I know it helps me.
Robert
1G cars have cups that are held to the axles by bolts.
2G cars have a rear axle that is held in by a nut. The axle slides into the diff, the wheel side of the axle is slid through the knuckle assembly and held in by a nut. This is much like the front axle design.
1g 90-91 rear service info.
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2g 97-99 rear service info.
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One sure fire way to check the rear is to count the ring and pinion gear teeth. By doing this you will verify and have no doubt of what rear you are getting. You can see above that all years (90-99) use the same gear reduction type. All manuals use a 3.545 reduction ratio while all automatics use a 3.307 reduction ratio. Drive gear teeth and pinion gear teeth vary based on AT or MT and viscous LSD or conventional diff. Use the chart above to find out what diff is in front of you.
I do not know any of the codes on the rear diff covers. I know that the combination on the rear diff cover is not a sure fire way to check the diff, but it would be a good fast check. If you know the codes (B1G, B1H, B1J) and which vehicle they belong to, that would be great. Any additional info would be great. Hope this information helps others and I know it helps me.
Robert