AAA:Replace worn tires at 4/32nds inch tread depth

[Shannow]

Originally Posted By: LotI
AAA


The full report for those who like facts. One of the objectives of the study was to find if value tires performed differently than expensive tires.


That's an impressive set of data.

Thanks

 

[krzyss]

Michelin Premier A/S beats all others in performance numbers when new and when worn.
Goodyear Eagle was designed for 'Uneven Concrete' based on its noise data.

Michelin equipped Camry stops in 192.25ft when new vs 229ft worse contender.
Michelin equipped Camry stops in 247.01ft when worn vs 326.7ft worse contender.

New cheap better than old expensive.

Krzys

 

[Snagglefoot]

I bought a cheap thread wear indicator. Takes the guesswork out of it.

 

[nap]

Originally Posted By: krzyss
Michelin Premier A/S beats all others in performance numbers when new and when worn.


I'm curious about your choice from a comfort perspective. Which is what the "Grand Touring" tire category is supposed to address.

 

[CapriRacer]

Originally Posted By: LotI
AAA


The full report for those who like facts. One of the objectives of the study was to find if value tires performed differently than expensive tires.


What jumped out at me was the differences between brands (which was confounded by the exact model.) I know there are ways to sort out the effect model (brand) had, but while I am sophisticated enough to know they didn't use the technique, I am not sophisticated enough to do it myself.

Personally, I wonder how rigged the test results were. I note that the test was conducted at a Michelin test facility and I would guess that much of the equipment used was Michelin in-house equipment. Home field advantage?

On the other hand, the published results are saying that cheap tires are just fine - which I would think would NOT be what Michelin would want.

I also note that the test results were directionally towards more expensive tires being better, it just wasn't at a 95% confidence interval - and what I know about traction testing is that these things are highly variable, so it's not a surprise they didn't get 95%.

 

[krzyss]

It is quite possible that Michelin tires tested on Michelin turf will have some edge.
From performance and noise numbers it seemed that Goodyears did not belong to high end tires except the concrete surface noise levels that was the lowest.
Maybe they were developed on different surfaces.

I think objective was to show that worn tires suck at 4/32 in wet regardless of price point. In my opinion they showed that best wet tires outbrake the worst by 30+ ft and that is a lot, at least for me.

Krzys

 

[nap]

Originally Posted By: CapriRacer


Personally, I wonder how rigged the test results were.


The only unusual thing there that I noticed is that they shaved all tires to 4/32 regardless of how much thread they start with.

The Premier starts with 8/32 and is designed specifically to keeps sipes until late stages of wear.

The others start more generously at 10/32 or more and the sipes are erased earlier than 4/32.

Maybe they should have checked against a Continental with DWS markings and shave it borderline to making the W (wet) marking disappear. As that is the clear indication from the manufacturer on what the thread depth should be in order to guarantee the wet performance.

Or maybe they should have shaved 4/32 FROM all tires (instead of shaving TO 4/32).

You can easily notice the differences from the pics.

 

[supton]

Flipped through the report. At the risk of being rude... even Michelin didn't do that well. Once worn, even the worst cheapo tire did better (when new).

Good testing, but IMO it opened up a new question, at for me: what does the curve look like, as one goes from full depth to mid depth to 4/32? Is 6/32 really close to new--or is it half between?

 

[SirTanon]

This video is an interesting analysis of the AAA study.. If you haven't watched this guy's channel before, it's definitely worth checking out.