Wear on backside of tread?

I’m going to run the risk of sounding like I’m going crazy and attempt to explain...

So I have had the Nitto Ridge grapplers on my truck for a couple months now. I would guess right around 3,000 miles. And having paid a good chunk for them, I feel little anal about wearing them out...

I noticed the other day that the two front tires are wearing a good bit faster than the rear. But specifically just on the backside of the tread.
The frontside looks brand new. SEE IMAGES BELOW.

I had the truck aligned at a reputable place yesterday and the final numbers were-

Camber- +.6 Left, +.3 Right
Caster- 2.3 Left, 2.5 Right
Toe- +.06 Left, +.05 Right

Is it normal for the tread to wear that fast on the backside? And if not, what could be causing it? Do those alignment numbers need to be further tweaked? (Specifically have the camber dropped closer to the ideal +.1)

 

Rotate and compare in another 3,000 miles.

 

How many miles are on your front shocks? Worn-out shocks will cause tires to "cup" (uneven wear). It's hard to tell by the photos, but this could be cupping due to worn suspension components.

 

At this point, that’s the plan! Crossing my fingers....

They have the same miles as the tires. 3k’ish... so I sure hope it’s not them...!

 

More important question is what was your alignment BEFORE they fixed it. Fixing it only matters from here on out, your tires are worn due to the numbers before. They look cupped, scalloped based off what you are saying and showing. That would be a product of worn out suspension or a poor toe set.

 

Since the shocks are new, sounds like @14burrito is probably right, it is likely due to poor alignment. It is also possible to get cupping on your tires due to worn suspension components besides shocks such as ball joints or bushings. If your "before" numbers on the alignment record sheet are within spec, I'd have a close look at your ball joints and bushings.

 

These trucks eat tires. Try rotating every 1.5k miles. Rears to front. Front to diagonal rears.

 

Certainly. I do agree there. That said, alignment only seems to have changed things about .1.

 

My best tire wear is when I cross rotate every 2.5k.

Definitely onto something with higher rotation frequency.

 

You pos camber isnt helping either.

Anyway you can get them to 0 camber, with toe close to .12 cross?

What's your frequency on tire rotations?

 

Sound’s like I need to get rotating...
I have noticed that these trucks toast front tires...

 

I am afraid that they may charge me again, but I do think that I’m going to call and see if they will tweak it for me...

 

What's your rotation mileage been up till now on these tires?

 

Tires have only 3k miles. So the first rotate will be today.

 

Purely curious, what's your typical use like on tires?

Because, based off what I see, after 3k tires looking like that....ridge grapps may not be on high on my list for new tires.

 

For the most part, it’s all highway and city miles. There have been a couple off road days in there, but I would expect to see more chunks taken out more than that kind of wear...

Yeah...but with having seen so many people with good luck...I’m a bit at a loss. Suspension has 50k on the clock and that was all highway.
The only thing I can think is that its wonky alignment...so I guess I need to keep playing with that. It’s just weird because while it may not be dead perfect alignment, it’s definitely well within spec.

EDIT- Also what is strange is that the passenger side has the worst wear. And the alignment numbers were best on that side. Camber was twice as high on driver, but that wear isn’t as bad...