Rear axle nut
 

WhT size is the (and thread) is the nut that holds the rear hub on.
Thanks
Dick

Re: Rear axle nut
 

5/8 -18 suffix S18 case hardened -from the ford parts book

Re: Rear axle nut
 

Don't forget to use the hardened washer.

Re: Rear axle nut
 

In case you are trying to find one in a local hardware store DON'T DO IT. They are a special very hard nut and need to be replaced with one from a reputable supplies of Ford parts.

Charlie Stephens

Re: Rear axle nut
 

I bought "hardened" washers for the rear axles from one of the major Model A part suppliers and they weren't hard at all. I went to the local Caterpillar dealer and got good hardened washers.
BTW, don't forget the seal that goes in the end of the hub before putting the washer and nut on.

Re: Rear axle nut
 

I assume you called them and requested a refund? By the way, who was the major supplier?

Charlie Stephens

Re: Rear axle nut
 

Where exactly is the requirement specified for the A-22371 5/8 Plain Washer to be hardened? I find that the A-21892 5/8-18 Castle Nut is specified as hardened, but not the A-22371 Washer.

By the way, I find from experience that the threads on the rear axle shafts are relatively ductile in comparison to the nut. It makes sense for the nut to be hardened because it determines the strength of the brake drum retention.

Re: Rear axle nut
 

If a hardened steel washer can't easily be found, can't a regular steel washer be case hardened by heating it cherry read with a propane or acetylene torch and dipping it in used motor oil (or any oil including vegetable oil)?
Rusty Nelson

Re: Rear axle nut
 

Wrndln, I think many repeated heating and dippings might be needed to get any usable case thickness.
I am interested to hear from someone who has tried this.
I have always used Casenit cyanide powder, or packed in charcoal and put in a furnace for many hours to get a decent case depth.
SAJ jn NZ

Re: Rear axle nut
 

I don't think "hardened" is what we need at all. High tensile is more like it. The objective is to prevent it distorting as the nut is tightened. Case hardening will help but not nearly as much as a washer made from high tensile material. JMHO.

Re: Rear axle nut
 

I'm with Synchro909 on this - where there is torsion, tensile strength is the key.

Re: Rear axle nut
 

There is no requirement for a hardened washer that I can find in any Ford literature!

In my opinion, hardening causes embrittlement and that is undesirable in a part subjected to bending as is the washer in question. Stop over-torquing the axle nut if the washer is being damaged.

Re: Rear axle nut
 

That's your opinion, others may vary.

Re: Rear axle nut
 

A soft washer will deform and overly squash the fiber washer when the nut is tightened, that's why a hard washer is preferred. Just because Ford didn't specify a hardened washer doesn't mean it's not a good idea.

Re: Rear axle nut
 

Thanks I have a new nut and the washer just needed a die for the threads on axle
Thanks
Dick

Re: Rear axle nut
 

Do not use a die on the threads, it will remove metal! Use a thread chaser, it is designed to reform the threads without cutting away any material.

Re: Rear axle nut
 

OK found a thread file, I'll try that
Thanks
Dick

Re: Rear axle nut
 

McMaster Carr has a number of different washers and nuts. I bought some hardened nuts to use when using the hub puller so that I would not distort the end of the axle. I modified one by using a Dremel cutoff wheel to cut a slot along the length of the nut and used this as a thread chaser. If the threads are in really bad shape, perhaps being distorted by using a hub puller without a backup nut, then a hardened nut can be cut in half with the Dremel and clamped on the threads and then screwed off to restore the threads. If the threads are not in very bad shape then the castle side of the standard nut can be screwed on first to restore the threads.

As a reminder, check the torque on the nuts every year or so depending on how much you drive your car.

Re: Rear axle nut
 

This set https://www.toolsid.com/lang-tools/2...-mpn-2581.html also has a die to chase the threads.

Re: Rear axle nut
 

How does the cotter key go on the axle steeped nut ? Should the legs be crimped over the axle end or in to the steps?