"Severe usage" axles had fine threads for the nuts.

They are 3/4-20, "extra-fine" (unless you have an "SU" axle...I don't know what that would be). You won't find them at Lowes but they can be found if you look hard enough. Are you missing one or looking to "chase" a damaged axle thread?
Frank

Frank
Thanks for your info. I'm trying to "chase" axle threads. I was doing a brake job on my '53 Hornet when I removed drivers side all went well then I went to remove passenger side & found that instead of the "normal" castle nut I found a "flat" nut that had a groove cut in the top so as to accept a cotter pin. I got an axle nut from Lance but it would not go on either axle shaft thus I thought there might be different thread counts. How do I identify whether I have a "Severe Usage" or "normal" axle & if I have the "Severe Usage" axle does anyone know what that thread count. I might be looking for a nut if I can't get Lance's nut to work.

thanks again for help

J

Buy a thread gauge and measure it. I have a Starrett #40 which goes from 9 tpi to 40 tpi.

Ed
I did measure the thread count & (as best I could) came up with 3/4"x18 but so far no one has verified this. Does this mean that the normal axle thread count is 3/4"x20 (as Frank suggests) & because I measure mine @ 3/4"x18 I must have the "severe usage" axle?

regards

J

J,
The parts book says the thread is 3/4-20 in both cases but gives a different part number for the SU version. The standard version is an old five-digit number, 71577, and was used up 'til '54 (although the number may have changed). The washer under that nut is the same part number for both the standard shaft and the SU shaft, leading me to believe that the thread diameter is the same. I suspect that the difference lies in the thickness of the nut. An axle for "Severe Usage" wouldn't be improved by additional thread diameter. The issue was shaft breakage likely at/near the area just outboard of the wheel bearing. That's my theory and I'm stickin' to it.
Frank

I was just about typing out a long reply when I checked Franks last reply. If the nut you got from Lance fits one side but not the other, then someone "worked" on your axle. I agree with Frank.

BTW It's pretty hard to measure thread size without a gauge.

In the absence of a thread gauge you can hold a bolt of known thread pitch up to your mystery thread for comparison. Such as: A 1/4-20 NC for 20, a 5/8-18 UNF for the 18 tpi , a 3/8-16 NC for 16, and on and on and................
Frank

Ed, Frank

I do have a gauge. As I said earlier as best as I could gauge it I came up with 3/4"x18 but it could be 20. I have a feeling I'm going to have to pull the shafts & have them welded up & re-threaded. Does anyone know where I might beg borrow or steal a shaft puller described in the shop manual?

thanks to all for the help

J

J

Here's a recap
You have 2 different types of nuts on your axles. All this means is that someone used whatever was available at the time.

Lance sent you a nut that does not fit either side. Do the 2 nuts you have interchange?

Frank says that both regular and su nuts are 3/4 - 20. This appears to mean that your axle is not su since Lance's nut doesn't fit.

You could try buying a 3/4 - 16 nut and see if it fits your axle, or you could take your nuts to a machine shop and get them to ID the thread.

A correct nut won't fit because forcing the incorrect nut onto the axle thread has damaged it to the point where nothing fits. It [i]is[/i] 3/4-20 and there are only two ways to correct the situation: Replace the axle with an undamaged one, or have the bad one welded up, turned back to .750" and rethreaded to 20tpi.
If you go back to J's original posts he said that one side was OK and the other was screwed up. I'll bet the OK side will accept the 3/4-20 nut just fine.....errrr, I mean, [i]extra fine[/i].
F

Frank

In his first post he said one nut was castellated and one wasn't. In a later post he said that the nut he got from Lance did not go on either side,. I doubt Lance sent him the wrong part. but it's possible. If he can't figure out what's going on he should just get new axles from Lance or leave everything the way it is.

You are right, he did say that the Lance Nut wouldn't fit either side. That makes no sense to me and doesn't match anything I have ever seen on a Hudson nor what the parts book says, so......I give up.
Frank, out.

Don't give up yet Frank. He has a Dana 44 right? Suppose the guts are from another make, like Chrysler?