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Old 03-26-2015, 11:57 AM   #18 (permalink)
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Originally Posted by oil pan 4 View Post
I was wondering if 3.21 is a type-o, but looks like I was looking for the wrong ratio. I found parts referencing that they work with "3.21, 3.42, 3.73 and 4.10" gear carriers.
Kind of like trying to find 4.11 gears, when they never made them, but always had 4.10 gears.
So thank you, I am use to 10 bolt stuff which has 3.23 gears.
I will look for 3.21 gears if I cant find any I will go with 3.42 gears.
I don't have to have new gears, I could go for a used set.
Actually, in my salvage yard Saturdays, I have found 4.09:1, 4.10:1, and 4.11:1 gears in GM 10.5s. Some genuine GM, some aftermarket, but all exist. And really, it doesn't matter that greatly which you end up with, even if you have a 4X4 with a front axle 0.02:1 off.
The 3.21:1s are most likely found in C20 C6Ps, but sometimes in C30s. They only came behind 454s, they were mid-'70s to mid-'80s, and were used behind SM465s and TH400s.
This info comes from GM's heritage center.
I've been seeking a set of 3.21s myself, no luck in the last year. The tooth count is 45:14
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