Rusted bolt rear diff pinion mount
Thread Starter
4th Gear
Joined: May 2021
Posts: 4
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Rusted bolt rear diff pinion mount
I have a rusted bolt that goes through the differential housing that holds the pinion bracket. I have sprayed it several days and cannot get it to budge. I should mention the previous owner rounded the hex head and welded the bolt. I ground the weld off and can rotate the bracket on the bolt shank. I have used an air hammer to drive the bolt out and torch heated the diff housing and still can’t get it to budge. I don’t want to remove the differential. The bolt is hard so you can’t drill it. Any suggestions will be appreciated.
Thread Starter
4th Gear
Joined: May 2021
Posts: 4
Likes: 0
the nut end is there and I tighten it and used my oxy torch to heat. I tried to tighten the nut when heated to draw the bolt out and it wouldn’t budge. My next step was going to be the torch and air hammer.
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From: Connecticut, USA
I had a 78 diff in one time and the bracket was still on it. Not a big deal until I found the bolt was also seized in the housing hole. I cut the bolt head off and tried to drive out the bolt but no go. I set it up in the mill and tried to drill it out but it was hard in the center and dulled the drill, tried an end mill and it rolled the edge of the cutter. I machined a punch to fit in the hole I was able to start before hitting the hard spot. I used a oxy/ace to cherry the housing and gave the broken bolt a shot, that loosened it up and didn't damage the housing.
Last edited by GTR1999; May 29, 2021 at 12:18 AM.
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Can you fit a second nut on the threads and use it as a lock nut? that way the next time you heat it it will act like a bolt head so you can rotate the bolt. Good luck
scott
scott
