Differential Bolt Size
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7th Gear
Joined: Feb 2023
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Differential Bolt Size
I cannot find the answer to what must be the closest guarded secret on the internet. What is the size and under head length of the 4 bolts that hold the differential carrier in place? Also, does anyone sell replacement girdles that hold the carrier in place? I'm trying to gather parts for a rebuild before I take everything apart. Thanks.
Melting Slicks
Joined: Nov 2006
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From: Apple Valley, MN
Melting Slicks
Joined: Nov 2006
Posts: 3,409
Likes: 1,821
From: Apple Valley, MN
9/16 x 12 x 3 3/16” are the bolts that secure the spring to the cover. You need to be very careful not to install anything longer as the longer bolts will bottom out in the forward two locations on the cover.
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Joined: Nov 2023
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I think the OP is asking for bolt sizes for what you'd normally call the bearing caps. Never had mine apart so I don't know the size. As far as replacement caps go, I'd assume the caps are bolted in place and then the assembly is bored when manufactured, same as engine main bearing caps. If that's the case, replacements (if available) would require machining to match the existing parts.
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Melting Slicks
Joined: Nov 2006
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From: Apple Valley, MN
Pro
Joined: Jun 2023
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From: Western N.C.
I cannot find the answer to what must be the closest guarded secret on the internet. What is the size and under head length of the 4 bolts that hold the differential carrier in place? Also, does anyone sell replacement girdles that hold the carrier in place? I'm trying to gather parts for a rebuild before I take everything apart. Thanks.
Tech Contributor
Joined: Aug 1999
Posts: 15,173
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From: Connecticut, USA
The bolts are the size mentioned- 7/16-14 x 2.250" However, every cap should be checked for correct fitment. MOST times, if original, they're good as long as they are kept on the same side. Sometimes they are not correct, other times conmen or people who should not work on these mix and match things, including bearing caps.
There is no secret to the bolt size unless you are rebuilding a diff that didn't have caps to start with and then you have to fit caps. Caps from one diff to another can be off 010-015".
There is no secret to the bolt size unless you are rebuilding a diff that didn't have caps to start with and then you have to fit caps. Caps from one diff to another can be off 010-015".
Tech Contributor
Joined: Aug 1999
Posts: 15,173
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From: Connecticut, USA
The caps won't be in bad shape if original. When people start messing with the diff, that's another story. The stock caps are fine once fit unless you plan on drag racing, in that case you may need a steel cap- left side only.
Thread Starter
7th Gear
Joined: Feb 2023
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Just a stock rebuild. When the rear gets warmed up, it starts clunking around sharp corners (like it has a spool in it). Despite throwing positraction additive at it, I think the clutches or something are wearing out.
Pro
Joined: Jun 2023
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From: Western N.C.
Tech Contributor
Joined: Aug 1999
Posts: 15,173
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From: Connecticut, USA
The differential should not clunk, hot or cold.
That sounds like posi chatter, if you used 2 bottles of additive and did the figure 8's in a parking lot and still have the chatter then it's in the posi setup. A good inspection of the diff before and during disassemble will typically show the issue. How the posi is built and the clutch type used will also play a big part in it.
That sounds like posi chatter, if you used 2 bottles of additive and did the figure 8's in a parking lot and still have the chatter then it's in the posi setup. A good inspection of the diff before and during disassemble will typically show the issue. How the posi is built and the clutch type used will also play a big part in it.
