'40 Rear end axle help
 

I'm in the process of rebuilding a '40 rear end and was able to get most of the parts needed. Both axles have acceptable tapers (I'm told by folks that know), but the threads on one of the axles are bad and it has been recommended to replace it.

So I can use some help in locating at least one axle, two would be better.

The part # is 81A-4235, 16 tooth axle, 32.85" in length

Must be very good condition NOS or very good used.

Appreciate help in locating these axles. Thanks.

Re: '40 Rear end axle help
 

Mig, Those (folks that know) should have also examined the keyways on those tapers for cracks that are present in a large percentage of used axles. They should also have given you the good news that you may substitute those described axles for earlier axles having the same dimensions but with 18 teeth, (if you also use the spider gear that goes with the 18 tooth axle set).

Importantly also, if you plan on saving a bunch of money by building the diff set yourself, come back here for detailed instructions regarding the preferred brands of beer to keep on hand during the build.

Re: '40 Rear end axle help
 

You should add your general location to your profile, it might pay off. Regardless of the condition of the axle I would run safety hubs or clips on the brake drums, cheap insurance.

Charlie Stephens

Re: '40 Rear end axle help
 

Thanks for the tip on the 18 tooth axles, we'll explore that route if we need to. Luckily I have some very experienced Ford folks near by and one that has assembled these many times, so I'm hopeful it will go smooth once we have all the parts. And beer is always on hand for anyone that comes to help.

Re: '40 Rear end axle help
 

Thanks Charlie, I'll update my profile. I'm in the San Francisco Bay area, town of San Ramon, CA. Axle retainers - yes, we have them already, appreciate the tip.

Re: '40 Rear end axle help
 

Check with the Early Ford Store in San Dimas CA. In his store are more axles than I've ever seen in one place. All tagged and for sale.

Re: '40 Rear end axle help
 

And, I've always liked dealing with them (Bill & Michael), and, they have always had whatever it was that I was looking for. They ship, and they will stand behind something like axles. If one slips through that, for example, has a crack in the keyway, they will replace it, cheerfully.
JMHO

Re: '40 Rear end axle help
 

Thanks Krylon32 and bobH. I contacted Bill at the Early Ford Store and he was very helpful. I have an axle on the way.

Bill told me that he sued to have hundreds of these but that has dwindled to a small number of them. The best he could locate from his pile was an axle that was an 8+ (on scale of 1 to 10). He did not know of anyone remanufacturing them yet but the day may come he said because the demand is still there. I was thinking that the old 'bad' ones can be rebuilt - by building up the taper, keyway and threads, and then re-machining them; probably have to go thru heat treatment too.
I now have 3 axles that are candidates for that.


Thanks again for the help.

Re: '40 Rear end axle help
 

Mig, a little info for you here on checking the condition of your axles: There are several things to inspect for:
Taper Use a flat file to knock down any burrs.
Keyway should have sharp edges, without wear marks, to hold the key from slopping around. Look closely for a crack at the inside end of the keyway, if there is even the smallest crack, the axle is scrap iron.
Grease Seal should not have been necked down.
Threads should be in good shape, and not mushroomed over.

It's a good idea to use some grinding compound on the taper/hub without a key installed. Put on the nut just far enough to hold the hub from falling off while you spin it to lap in the taper. Clean off all compound, reinstall dry with key, torque to 150-200 ft lbs., install the cotter key.