Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 01-10-2026, 03:18 PM   #1
Tim Ayers
Senior Member
 
Join Date: May 2010
Location: NJ
Posts: 7,227
Default Difference with two banjo rear spider gear housing/ring gear bolts

I'm in the process of getting ready to build up another rear end. I had a '40 rear that I was hoping to take the axles from. Turns out the gears are pitted by sitting in gunky grease.

When comparing two different center sections that I have, one of them has the bolts with safety wire holes drilled into them and castle nuts.

The other carrier does not have safety wire holes drilled and is topped with those "self locking" nuts. Both bolts are correct with the D shaped head

I'd think the safety wire set would be preferred in something like a rear end. If so, I'll swap them over to the carrier I'm planning to use for this conversion.

Thoughts?
Attached Images
File Type: jpg Rear diff bolts 1 .jpg (52.2 KB, 79 views)
File Type: jpg Rear diff 2.jpg (53.7 KB, 76 views)

Last edited by Tim Ayers; 01-10-2026 at 03:43 PM.
Tim Ayers is offline   Reply With Quote
Old 01-10-2026, 04:29 PM   #2
Bruce_MO
Senior Member
 
Join Date: May 2010
Posts: 592
Default Re: Difference with two banjo rear spider gear housing/ring gear bolts

I’m no expert on fasteners, but my experience with the Marzden nuts in your first photo is that used nuts don’t seem to have much of a “locking” feature after having been installed. I’ve never had any back off yet (new or used), but they sure seem to go on all the way with no change in resistance, definitely not feeling like they’re locking and won’t back off. I have assumed that the split tops on the nuts were maybe upset a bit to provide resistance to backing off, but maybe they resist loosening by some other means. Would love to be educated on that.

Bottom line is I’d use the castle nuts and safety wire for that application, and any others where loosening would be a big failure.
Bruce_MO is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 01-10-2026, 04:30 PM   #3
Brian
Senior Member
 
Brian's Avatar
 
Join Date: May 2010
Location: Masterton, New Zealand
Posts: 4,097
Default Re: Difference with two banjo rear spider gear housing/ring gear bolts

Yes, the earlier style used the castle nuts and safety wire, post war they went to the self locking nuts and eliminated the holes in the bolts for the wire. Like you, I prefer the earlier version, but instead of lock wire I just use split cotter pins.
__________________
Unfortunately, two half wits don't make a whole wit!
Brian is offline   Reply With Quote
Old 01-10-2026, 04:39 PM   #4
Bruce_MO
Senior Member
 
Join Date: May 2010
Posts: 592
Default Re: Difference with two banjo rear spider gear housing/ring gear bolts

Sorry for mis-spelling Marsden. Just googled and saw that the design is that the nut goes on all the way until it hits the base, and then further tightening “deforms the nut into the threads of the bolt” for a secure connection that can handle vibration. So maybe reusing them might be unwise.
Bruce_MO is offline   Reply With Quote
Old 01-10-2026, 07:31 PM   #5
petehoovie
Senior Member
 
petehoovie's Avatar
 
Join Date: May 2015
Posts: 11,644
Default Re: Difference with two banjo rear spider gear housing/ring gear bolts

Sponsored Links (Register now to hide all advertisements)
Quote:
Originally Posted by Tim Ayers View Post
I'm in the process of getting ready to build up another rear end. I had a '40 rear that I was hoping to take the axles from. Turns out the gears are pitted by sitting in gunky grease.

When comparing two different center sections that I have, one of them has the bolts with safety wire holes drilled into them and castle nuts.

The other carrier does not have safety wire holes drilled and is topped with those "self locking" nuts. Both bolts are correct with the D shaped head

I'd think the safety wire set would be preferred in something like a rear end. If so, I'll swap them over to the carrier I'm planning to use for this conversion.

Thoughts?


__________________


petehoovie is online now   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 03:20 PM.