Author Topic: Rear diff compatibility  (Read 2070 times)

Offline TexasRed

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Rear diff compatibility
« on: May 16, 2011, 08:04:24 pm »
Here's the issue, I have a 84 sierra classic (c1500) with 2.73 rear end and I'm trying to locate a whole assembly with either a 3.42 or 3.73 rear end. Is that possible or am I stuck with swapping out what I have? Did anything come stock that'll be a direct bolt in for my application with those ratios?

Offline VileZambonie

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Re: Rear diff compatibility
« Reply #1 on: May 16, 2011, 10:25:22 pm »
Any C10 or C15 73-86 R10 87 will be a direct bolt in. The 81 up will most likely be a 10 bolt while the 1980 down will typically be a 12 bolt which will require a conversion U-joint. The brakes may be different as well. Typical ratio's are 2.56:1, 2.73:1, 3.07:1, 3.08:1, 3.42:1, 3.73:1
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Offline Blazin

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Re: Rear diff compatibility
« Reply #2 on: May 16, 2011, 11:14:39 pm »
You can swap the 10 bolt backing plates onto the 12 bolt and keep the correct brakes for your year truck.
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