GTR rear shaft hub nut/thread

[Old man 32 GTR]

Having a slight issue with the rear shafts in the GTR. Car 92 R32 GTR
min the course of my build I had the rear shafts sent away and rebuilt, now when removing them the shop told be they had trouble getting the nut undone and one of them was destroyed, the other is rounded off,  I bought a set of replacement nuts locally, but they didn’t fit and I was told I need GTR specific nuts, so I ordered genuine rear hub nuts from Kudos, these came from Japan, problem… they still don’t go on, I’m thinking maybe the thread has been damaged possibly from over tightening. 
I can get the new nut to start, but it’s really tight. 
I took the original nut that came off to a nut/bolt shop to see if they could supply a new one but they had nothing in that size/thread pitch. 
the original nut that came off does go back on but it also a little tight and does not wind  on easily. 
I then went to total tools to get a thread cleaner, but they don’t stock anything in that size, I ended up buying a thread file and will have a go at using the file to clean the thread. 
Am I missing something? 
Is there a different nut I need? 
My next step is to go to a drive shaft shop and see if they have a nut that works/fits. 
Or is it Most likely the thread is stretched/damaged? 
By eye, the thread looks fine 

I’ve attached some pics, you can see on the new nut the thread has been damaged from trying to force it on. 
cheers 

[GTSBoy]

7 minutes ago, Old man 32 GTR said:

Or is it Most likely the thread is stretched/damaged?

This. If it's anything, it's this. You need a thread gauge and/or a decent machinist who is accustomed to measuring threads to have a close look to see what might have happened. Overtightening will lead to thread stretch. Usually behind the nut though.

[Duncan]

Couple of things

The thread on the nuts is the same from both sides, so you can thread the nut on backwards to try to get started again with clean threads...obviously you can't tighten it up that way.

I had a similar issue with a borrowed evo at targa years back, what we did was grind the last couple of threads off the driveshaft with an angle grinder (what we had) although a linisher would be better. Just to put a 45o approach for the nnut instead of going straight to thread.

if you want to try and get a correct sized die (won't be cheap) a truck supplies shop would be the way to go

[Old man 32 GTR]

18 minutes ago, GTSBoy said:

Overtightening will lead to thread stretch. Usually behind the nut though.

This is what I thought, wouldn’t thread stretch only be thread behind the nut, and it’s the same on both sides. 
Can someone confirm is the front and rear thread pitch and size the same? Because I was told they are different but the nuts I bought go perfectly on the front shafts, but if you check the part number, they are listed as rear. 
I’ll head out to total tools tomorrow and grab a thread gauge, or are the generic ones useless? 
this is the thread file I got, was the only one they had in metric. 
 

[Old man 32 GTR]

23 minutes ago, Duncan said:

Couple of things

The thread on the nuts is the same from both sides, so you can thread the nut on backwards to try to get started again with clean threads...obviously you can't tighten it up that way.

if you want to try and get a correct sized die (won't be cheap) a truck supplies shop would be the way to go

I’ve tried your first suggestion, still is super tight. I’ve got 4 x new nuts that are the same so I could destroy a couple if needed. 
if I get off work early one day next week I’ll try a truck supplies shop and see how I go with the die, if I can’t get it sorted before hand. 
I wish the shop told me there was an issue, I would have got it sorted while the shafts were out of the car! 

[Old man 32 GTR]

And talk about targeted advertising! Lol 

 

[Duncan]

yeah that would have been nice....and much easier....

BTW I don't know what size the thread is (feel free to post it up for posterity once you work it out :)) but big dies are expensive unfortunately

I think the front v rear difference is the rears have a flange and the fronts don't. No idea why or what difference it makes once there is a washer in place and the nut torqued correctly.

[33GTRV]

pretty common. 

 

Some people flog the end of the shaft with the inside of the socket when using an impact, and due to the cotter pin hole on the shaft, this area deforms very easily. get a nice file, run a small chamfer on the leading edge and try again.

 

I have a few spare shafts (broken ones) in the garage. Im back in town on monday, i will have a squizz and let you know the thread sizes.