Why are my tires wearing out like this

I'm not sure your problem is the tires, is it all of them on back doing it? Whether or not you can run them the rest of the way down depends, they throw a belt, are they maybe horribly out of round, I wouldn't think that's the problem or you'd feel like you're riding a jackhammer down the road. Like has been said, get them balanced, either centramatics or the normal way, run them awhile and see if they get better or worse, get the alignment and suspension back there checked out too.

 

This ^^^ You have an issue that needs addressed somewhere, it’s not the tires. My brother runs a fair amount of gravel roads, is usually heavy, and can still get over 200k out of a set of XDN2’s. Unless you’re happy ruining tires I would spend the money to find the problem.

Where did you say you are located?

 

GCR in Oakland is shown as being an MD Alignment shop. I’d start there.

 

I would start from freightliner dealer. OEM Sachs or Freightliner branded shocks.

 

I would start with an alignment shop. A reputable one that will check every bushing in the backend of the truck. I wouldn’t start at a dealer. They will throw parts at it and end up sending it out to an alignment shop anyway.

And it could very well be a combination of a lot of things. You’re tires could be overinflated for the weight you haul, your shocks could be wore out, your torque rods could be shot, and you may need new bushings on the suspension hangers.

 

OEM shocks do last a very long time. I had one go out after 600k. Now I have Monroe (gas and oil shocks). They feel better, but who knows how long they’ll last. I’ll probably thoroughly inspect them at 200k. For now I just look at them, but I think I’ll check the temperature on them with my laser temp gun one of these days.

 

ReCheck with a dial or stick gauge, those digital gauges are notoriously inaccurate.
And check all 8 tires...

 

Agreed.
Line energy D are a 400k+ mile tire when things aren't screwed up somehow.

Shocks should always be changed at 100k or sooner. I usually change at 60-80k as the dampening is noticeably less effective. No leaks but the ride is noticeably off ... Especially starting out the truck will have increased torque twist effect on the body.

Those digital gauges are junk to measure pressure, have seen way too many that read totally incorrect.

 

I run those tires at 120-125 and haul 50% at gross and about 50% at 60-65k lbs. They run cool and wear amazing.. like iron.

 

I’ve never heard of anyone changing them so soon. Monroe has a video on YouTube where they mention that fleets tend to change them at 200-250k, and in off-road use, they replace them sooner. Monroe also mentions how to inspect them.