rear axle nut difficulties

[vb7prog]

so I took bike to shop to get new rear tire, and they tightened the chain too tight, but I know the procedure and its hasn't been too big of an issue, so I decided to fix at home. Here is the issue:

I have an impact wrench 425 ft-lbs of force, when I try to undo the axle bolt, it spins, so I use the 34mm helper wrench for the other side, but the torque gun wants to spin the helper wrench so I have no way of applying useful torque without seriously hurting my hand/fingers, at 25 ft-lbs the helper nut spins, but i cant get them unstuck, I have undone the nut in the past 2-3 times and this hasn't been an issue, what causes the nut to be so tight with the axle, how should i proceed?

 

[SandyN]

Very frustrating! The only advice I can give is to have someone help to get a decent hold on the bolt with a socket and power bar while you undo the nut.

I've twice had tyres changed and the bike comes back with the chain too tight. They give a free chain lube and last time the thread on the axle was sprayed with chain lube before they torqued it which caused over tightening and damage to the thread...

 

[vb7prog]

Very frustrating! The only advice I can give is to have someone help to get a decent hold on the bolt with a socket and power bar while you undo the nut.

I've twice had tyres changed and the bike comes back with the chain too tight. They give a free chain lube and last time the thread on the axle was sprayed with chain lube before they torqued it which caused over tightening and damage to the thread...

so I bought a proper socket (36mm) for the other side so I could use my breaker bar with good handle, and that allowed me to hold the axle helper side firm, but I pounded on in it with the impact wrench on the other side and it didn't budge, at this point frustrated, I decided to take it back to the shop that did the work.

they tried their best with 2 guys on long breaker bars both sides to get it off (spent like 25 minutes struggling with it), and they told me they got it off (I was skeptical, if 425 ft-lbs couldn't get it off how could their 2 ft breaker bars?) , but that I need a new axle pretty soon because this one is likely bad due to "neglect".

When I got home, I tested it again, and at 20 ft-lbs the nut would spin, but not come off, this tells me the shop didn't actually get the nut off, but didn't really want to deal with the problem.

so, I have an axle nut that won't come off with 425 ft lbs of torque, or two strong guys using pb blaster liquid and breaker bars, and the axle will spin with 20ft-lbs of torque. I think I probably do need a new axle and nut, but I feel like the bike is relatively safe to ride ? I don't really trust it but want to put off getting axle to next tire change. I am frustrated because it just seems like issue after issue with this old bike now.