Bent or Mispositioned Trailer Axle

I have a 2009 Montana 2980. I keep wearing out the left rear tire, about 2 inches of the inside like the camber is out of spec. The rest of it looks like new, about 8000 miles or less on it and all of other 3 tires look like new. I had it in the dealer where I bought it in Wisconsin just before my warranty was over and they couldn't find anything wrong with it but Keystone did give me a new tire and sent me on my way. I keep check on my air so I know that's not it. I wore another tire out in about the same amount of miles and am starting on my third one while the rest still look like new. Keystone had me take it to another shop and they told Keystone the axle was bent 2 feet in from that wheel. They claimed that I hit something with it. I know I didn't, so when I got the trailer home I put a straight edge on the axle and I checked the same on the front axle and they both come out with the camber on it, so I know that it is not bent there. This has done this with different rims so that is not it either. I do have another appointment with the dealer where I had it the first time but I don't know if it is going to do any good or not as they couldn't find anything wrong the first time. Please let me know if you can help me with this problem. The type of tire is a Goodyear Marathon 235/80/R 16 rated E. Thanks! Ervin P., (Seattle, WA)

So sorry to hear about your tire wear problem Ervin. That CAN get expensive if not corrected. Couple things...I'm attaching some Dexter Axle info sheets that may help your shop determine if that axle is indeed installed properly. There's an info sheet plus an installation guide. Also, you can request the actual service manual for your axles by going to this page on the Dexter site. 

It's quite possible the hub assembly and backing plate have been mis-positioned, probably during the initial installation, but it will require a detailed inspection and close measurements to be sure. That's why I'm hoping the installation guide will be helpful for a knowledgeable troubleshooter to verify.

I'm sure you're aware, but be sure the tire is inflated to the proper air pressure based solely on the weight that tire is carrying. A number of weight measurements are required to determine exactly how much weight each tire is supporting. Let me know if you need guidance for weighing your rig.

But after a close inspection and some crucial measurements, a good tech should be able to determine the cause of your uneven tire wear. I don't think the tire itself is the issue unless the inflation is incorrect for the amount of weight it is carrying. I'm guessing it's something peculiar to your trailer and that axle. Something in that alignment is just not correct. Of course, I know you're already aware of that!