OK, lets recap. This is a picture of the 1975 differential currently installed in our Corvette. When we tried to install the drive shaft we found out this differential uses a 3.7" diameter universal joint but we need one that accepts a 3.3" universal joint. Since we have a 1963 differential on the shelf, and it accepts the smaller universal joint, we decided to swap them out. But first...
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We need to remove a broken bolt, one of four hardened bolts that hold the leaf spring assembly in place. It's in the lower right of this picture and this is going to be a bear.
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A small pilot hole was drilled through the entire length of the bolt in order to get penetrating oil on both ends.
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The hole was enlarged, heat was applied, then I grabbed an Easy-out.
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A few whacks with a hammer to seat the Easy-out and we are ready for extraction.
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Looks simple doesn't it? Trust me, it's editing magic.
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With that repair behind us, the differential was cleaned as best as possible before heading to the sand blasting box. Pre-cleaning is done to keep the blast media from becoming contaminated with road grease and grime. It took 3 hours of picking, grinding, wire brushing, and wiping with solvent before it was ready. Just before blasting, kite string was wrapped down behind all 3 yokes to protect the seals.
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After sand blasting the strings were removed, primer was applied...
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followed by a couple coats of cast iron colored paint.
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It looks nice!
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Next posting should be the swap out the 1975 rear end for the 1963. Thanks for watching.
Update! After running the numbers it turns out the 1963 differential is really a 1965. Use the Poll in the upper right of this blog to help decide which differential we want to use.