Diff carrier bolts using self locking nuts
 

Has anyone used self locking, deformed thread type locking nuts on the diff carrier bolts?
One of our members wants to use these and any comments would be appreciated.
Thank you,
Al

Re: Diff carrier bolts using self locking nuts
 

No I have not used them and I do not know how bad they will leak.



The original threads were tight tolerance threads and should not be chased with a tap or die.

This allowed for 2 things. It would not allow the oil through and it would lock the bolts. A pretty simple solution by Ford to effectively prevent a problem.

I hand cleaned the threads on both sides. I had a pile of original bolts so I took the clean dry bolts and screwed each one in by finger. The ones that would go in further then 1/2 way I did not use as they were too loose. Some would go in easy all the way and the best would only get about 1/4 the way into the hole.

Of couse, some of the best fitting bolts were also the nasty rusty heads!! Yes, I used them as function is more important in some places.

Re: Diff carrier bolts using self locking nuts
 

I have done a few rear end assemblies the past two years. I feel qualified to comment on this question.
The carrier assembly, through the process of assembly and adjustment, needs to be assembled and taken apart a couple times due to the setting of pre-loads. Multiple assembly/disassembly wear on the nuts and bolts using interference lock nuts may impact the strength of the threads.

The other issue I see with using deformed thread lock nuts is the torque value would be off. My opinion is that it would not matter as long as you exceed the 35# torque normally spec'd for the carrier bolts. If I was using this type of lock nut, I would torque them all to 38#.

Personally, I would use original bolts, nuts and safety wire to avoid the possibility of inconsistent torque values. JMO
Good Day!

Re: Diff carrier bolts using self locking nuts
 

Hi Keven, Some confusion here - I'm talking about the carrier bolts comprising the differential and I agree with you about the axle housing to banjo threads.

Hi Dave,
---- through the process of assembly and adjustment, needs to be assembled and taken apart a couple times due to the setting of pre-loads.
My opinion is that it would not matter as long as you exceed the 35# torque normally spec'd doe the carrier bolts. If I was using this type of lock nut, I would torque them all to 38#.
Personally, I would use original bolts, nuts and safety wire to avoid the possibility of inconsistent torque values. JMO
Good Day!
We have done all the carrier pre-load and ring/pinion adjusting using the original bolts and nuts. The last time we button it up we are planning to use the locking nuts never to be removed again. The 38# torque makes sense.
Thanks gentlemen for you advice.
Al

Re: Diff carrier bolts using self locking nuts
 

Why?? You've got it where it's very simple to install the safety wire. FWIW

Paul in CT

Re: Diff carrier bolts using self locking nuts
 

I would feel safer with the locking nuts, instead of the flimsy "safety" wire. That stuff is a JOKE! Does anyone ever "safety" wire those 4 rear motor mount bolts? I'll bet NOT! By the time you hassle them bolts in, you're WORE OUT!
Bill Opinionated

Re: Diff carrier bolts using self locking nuts
 

A stud combined with a self-locking nut is a poor choice in any high stress location. The self-locking nut locks to the threads it is installed on, NOT the surface the nut is torqued down to. If the stud decides to loosen, then it will all come out. A nut safety wired properly will guarantee permanent attachment of all parts of the assembly. Ford knew this, anything wired on a ''T'' I personally would not change. The large recip aircraft engines I worked on in the AF vibrated tremendously, but nothing fell off due to safety wire breaking. Gary

Re: Diff carrier bolts using self locking nuts
 

This is the way I learned to safety wire things:

Re: Diff carrier bolts using self locking nuts
 

Well safety wire sure works on aircraft if it done right. You gotta wire it so that if a bolt tries to come loose it tightens the one it's wire to and so on. I spent 5 years in the USAF using it on aircraft and it sure works there. You can get stainless safety wire at aircraft supply places.

Re: Diff carrier bolts using self locking nuts
 

I would do all the set up and pre-load using regular nuts and when you do the final assembly, use the lock nuts. You may also want to use a little lock-tite just to be sure.
The 38#ft. torque value sounds good.

I would be comfortable with that arrangement.

Chris W.

Re: Diff carrier bolts using self locking nuts
 

And you learned the correct way to use safety wire.

Re: Diff carrier bolts using self locking nuts
 

Thank you all for your comments and thoughts.
One thing I like about the locking nuts is that you don't have uneven torque on hardware due to lining up the wire holes with the nut slots.
Al

Re: Diff carrier bolts using self locking nuts
 

use loc-tight

Re: Diff carrier bolts using self locking nuts
 

I thought the carriers could have studs or bolts, depending on the vehicle/year? Wouldn't be the first time I was wrong....

Re: Diff carrier bolts using self locking nuts
 

If you safety wire like CarlG's picture which is the only way to do it correctly. If done right you will not have " flimsy safety wire". People who just run a wire through the holes with out the proper twist and threaded so it is impossible to loosen as pictured have not been properly taught. That is not a put down. There are many things that I have not been taught correctly so have done improperly. Thanks to FB I have become aware of much that I just did not know. FB has saved me a lot of grief.

Re: Diff carrier bolts using self locking nuts
 

Getting even torques is not that hard, try another nut, add a thin washer, add a heavy washer, remove some metal from the nut. It just takes some time :-)

Re: Diff carrier bolts using self locking nuts
 

Mine are safetied with 0.041 stainless steel aircraft safety wire.

Re: Diff carrier bolts using self locking nuts
 

Yes mine are...

Re: Diff carrier bolts using self locking nuts
 

All the bolts are being replaced with new bolts and are a mild interference fit.

All the old bolts were wired with one piece of wire through all bolts without any twists.
The wire was about .050 diameter and bolts were not all at the same torque.

My four rear motor mount bolts are safety wired also but I would not get any point for craftsmanship.