Gas tank J-bolt locknuts shredding threads

[Coelacanth]

I'm replacing the gas tank in my '70 Charger and bought the repro B-body J-bolts & locknuts. The nuts have a little divot in one side. I noticed they wouldn't thread on after a turn or two so started reefing on it with a socket for another turn or two. It felt like it was cross-threading, though it wasn't, so I backed off and had a look. The J-bolt threads were basically shredded. I realize these are lock nuts but I wasn't expecting them to mangle the threads. Clearly any attempt at future removal would require major effort or even cutting the J-bolts off. Is this normal?

 

[RemCharger]

No. Just China metal. Find a non lock nut, or 2 and lock them together.

 

[Coelacanth]

Thanks. Those little divots in the sides of the nuts had something protruding on the inside, obviously obstructing them from threading on. I figured those might just be bits of nylon but they certainly weren't. Fortunately I backed off soon enough and an ordinary nut was able to thread back on the J-bolt with the mangled first few threads.

 

[Fran Blacker]

If not a restoration use a fiber lined nut.

 

[OKDart]

Looks like the nuts were manufactured incorrectly. The dimple should be just enough to create a slight interference fit.

 

[terrywalker]

I use anti-seize on nuts like that. If too tight, I have also used a starter tap to open the nut up a little. Otherwise use a regular nut and lock washer if not a restoration..
Terry W.