Lock nut

This week I brought a truck in for a service and I noticed the tire was waring unusually. Here is a picture 

 

It's hard to see in the picture but the fourth thread line from the left is worne out a lot more then the rest. The only reason this can happen is cause of the drivers bad driving, king pin, or bearing.

I jacked the truck up and used a rod to see if the tire moved for king pin play. There was a lot of play. So I removed the tire and hub cap. And I noticed there was an older style lock nut but it wasn't even locked in... I spun the nut off by hand. That is why the tire was waring bad and had play in it. Here are some pictures....

As u can see it isn't locked in. 

I installed the new style lock nut and torqued it to the right amount. I leanred how important it is to observe tire ware. We got really lucky, that tire could have came off going down the high way and killed someone. The lock nut was factory so it had been running that way for a very long time. Also I leanred how to tongue the lock nut by reading the directions. I usually tighten all the way to set the seal and back it off till the tire spins good. That's how I was thought. I think I'll tongue it next time. 

Hours 261