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?

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.

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.

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.

Re: Difference with two banjo rear spider gear housing/ring gear bolts
 

https://www.fordbarn.com/forum/attac...2&d=1768076283

https://www.fordbarn.com/forum/attac...3&d=1768076283