12 bolt GM truck rear

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muff

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I have rebuilt my 1981 C10 from bottom up. I had the Rear pinion seal replaced last week and the shop never tightened the nut that hold the driveshaft to the rear. Well the result was a dropped driveshaft 15 miles from the shop and a brocken tooth on the pinion gear. The current ring and pinion are 47 \ 17 which ratio to 2.76. This is an odd ratio but i heard they did make it and its rare. ANYONE have a spare or know where i can get a new one.
any comments or help are thanked in advance

Muff
 

89Suburban

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We hope to have somebody answer your question soon. I deleted your other thread since it was a duplicate. Did you go back to the shop and ask them to fix it?
 

muff

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i have gone back to the shop and dicussed what happened with the owner. He was very nice and apoligized several times. I explained to him that I no longer felt comfortable with there work. He is going to play the bill in full at another shop and refunded me all my money from the previous work they did. My only issue now is I cant find the 2.76 gears. I have a driveline shop near by and they told me good luck finding a set they have had lots of trouble in the past finding 2.76 gears. The last thing i want to do is replace both front and rear ring and pinions
 

GreaseDog

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2.76 gears are worthless in a truck. Regearing will probably pick up fuel economy and add power. Take this opportunity to put a good gearset in the rear, and find a matching front with the money you were refunded from the initial repair.
 

muff

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What gear ratio should i go with. Is there a brnad that I should go with? I see there are Yukon, Richmond,Superior and Motive Ring and Pinion sets. What is the difference other then price.
 
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Kapdin

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Is this a daily driver? do u every pull much?
 

muff

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I will be driving it often and very rare is it that i pull anything
 

crazy4offroad

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Richmond would be my top choice, followed by Yukon, and I would not recommend Motive to anyone. 3.42 would be a good ratio to consider. 3.08 is the pretty much standard gear for economy, and 3.73 for towing power so 3.42 would be a happy medium, depending on the tire size on your C10.
 

Kapdin

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:happy160: wat he said.
 

muff

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I have the 15" rally wheels with 31" tires. I also have a set of wheels that i use for the winter but they are also 15". Thanks for all the info. Hopefully I can help you out in the future.

Muff
 
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bucket

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I have the 15" rally wheels with 31" tires. I also have a set of wheels that i use for the winter but they are also 15". Thanks for all the info. Hopefully I can help you out in the future.

Muff

Daily driving, not much towing, no overdrive, 31's... 3.42 would be a very nice all-around gear ratio.
 

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