Separating Tread On All 4 Tires - How?

[ThumperRidgeline]

I would check to see when Firestone's alignment machine was calibrated. I have always had good luck at shops that specialize in alignments and/or that is all they do. Also, are you getting your tires Road Force balanced?

 

[Lethal1ty17]

Originally Posted By: ThumperRidgeline
I've run Michelins for over 50 years and never had an issue..They may cost a little more up front but service and tread life are great. I tried Goodyears from Tire Rack on my WS6 but could not keep them balanced. Found out Goodyear had a recall on them and Tire Rack tried to swap for another set of Goodyears...After going up the chain and finally speaking with someone who could make a decision TR exchanged for Michelins. They are now over 6 years old and have had no issues. Michelins or nothing...


You can just look at the treadwear rating if you want to compare how long the will likely last. Harder compounds go longer.
Originally Posted By: ThumperRidgeline
I would check to see when Firestone's alignment machine was calibrated. I have always had good luck at shops that specialize in alignments and/or that is all they do. Also, are you getting your tires Road Force balanced?


I just got the alignment rechecked at another place and everything is still spot on within spec. I cannot remember if they initially got Road Force balanced when they were mounted or not. I have a regular lifetime balance plan because they don't offer lifetime Road Force balancing.

 

[CapriRacer]

Originally Posted By: Lethal1ty17
……. I just got the alignment rechecked at another place and everything is still spot on within spec. …..


Allow me to comment on this.

Either the alignment was spot on or it is within spec (or out of spec), but it can not be both. The print out you posted says it is within spec, but not spot on - and that's the problem.

Given the amount of miles you put on, the alignment has to be near perfect to get even tire wear - and that's exactly what is not happening.

First, did you notice your steering wheel was not pointed straight ahead before they adjusted it? That's what that alignment print out says.

Second, the out of spec caster causes excessive camber every time you turn - which is where most tire wear takes place.

Yes, it is not uncommon for vehicle manufacturers to not provide adjustment for camber/caster - and that you have to either have a die grinder to free the top bearing so it can be moved, or have an offset bolt installed to get the suspension properly set.

Then there is the problem of not being able to rotate tires. My experience is that at 20K, alignments at the edges of the spec will start to see some irregular wear develop. You've got many more miles than that. Plus, the degree of irregular wear doesn't develop in a straight line. It is exponential! That is, it will be more than twice as bad at twice the distance.

And it doesn't matter if you fix the alignment, the tire wear that is already there will continue to get worse - because whatever the new pattern is, is put on top of the old pattern.

 

[Cujet]

Originally Posted By: CapriRacer
Originally Posted By: Lethal1ty17
……. I just got the alignment rechecked at another place and everything is still spot on within spec. …..


Allow me to comment on this.

Either the alignment was spot on or it is within spec (or out of spec), but it can not be both. The print out you posted says it is within spec, but not spot on - and that's the problem.

Given the amount of miles you put on, the alignment has to be near perfect to get even tire wear - and that's exactly what is not happening.



Then there is the problem of not being able to rotate tires.

And it doesn't matter if you fix the alignment, the tire wear that is already there will continue to get worse - because whatever the new pattern is, is put on top of the old pattern.


Last points first. You can rotate NONDIRECTIONAL tires Left to Right (across the car) . This can help mitigate small amounts of normal but uneven wear.

On front tires, the highest loading they see is often hard braking (city cars in particular) . Run a hand (front to back) over the top side of the tread of a (used) front tire on any vehicle. You will probably notice that the tread blocks are not worn evenly front to back. This is due to the leading edge of the tread block wearing faster under braking.

The rears can sometimes wear in an opposite pattern, as on many cars, they simply do little braking and otherwise just roll. (depends on model, FWD or RWD loading and more)

Alignment for highway driving includes LESS negative camber while retaining enough toe-in to prevent wandering. The high levels of negative camber induce high wear, and tire heating. HOWEVER, choosing 0.0 negative camber in the rear can lead to oversteer (rear swinging out during hard cornering) and loss of control.

Some early Tesla owners modify the rear suspension from a non adjustable -1.53 and -2.30 to -1.0 or even -0.5. This improves tire life considerably.

 

[Lethal1ty17]

Obviously I don't have the experience and expertise as some on here by owning or working in a tire shop or anything of the sorts. This is what I am going off of when I say the alignment is still within spec. That's all I have to go by.

 

[CapriRacer]

So the alignment is currently good - except for 2 items: The left front toe (My experience says the value needs to be within 0.06° of the target. It is 0.10° off.) and the rear camber. (My experience is that anything over 1° causes irregular wear. Yes, I know what the spec is. I'm saying my experience is that the spec is good for handling, but bad for good tire wear.)

However, that is what you have now. We know that it was worse earlier and it is that condition that caused the irregular wear on your tires.


If you arrange to fix the toe and the camber as indicated above, your next set will wear much better.