Outside edge of front tires stairstepping

On 7/8/2017 12:32 PM, Chaya Eve wrote:
> On Sat, 08 Jul 2017 08:10:53 -0700, Bill Vanek >
> wrote:
>
>>> Philosophically, is it a smart decision to definitely kill half of what
>>> you're trying to save, just to measure to see if it needs to be saved?
>>
>> You don't need to replace the tires to do the alignment.
>
> I must not have made the philosophical argument clear if you say that, so
> let me just outline a WORST CASE scenario (philosophically speaking).
>
> 1. Assume alignment is fine (for the worst-case scenario philosophically)
> 2. Assume front tires only are wearing on the outside edges (feathering)
>
> How much does a brand new tire cost, mounted?
> About $100.
>
> How much does an alignment check cost, on sale, where I live?
> About $100.
>
> That's a philosophical tradeoff of 1 mounted tire to 1 alignment check.
>
> The logic is thus:
> A. If the alignment is obviously bad, then it will cause excess wear to
> EVERY tire ever put on the front axle, so, of course, you have the
> alignment fixed because of the obvious cost:benefit ratio.
>
> B. However, if the alignment is actually ok, then it's not cost effective
> to have the alignment checked since the best you will do is save partial
> wear to the tires but at worst, you just threw away an entire brand new
> tire ($100) just to have the alignment checked.
>
> My point is that checking the alignment costs as much money as does a brand
> new tire, so, where would you rather put your money IF the alignment is
> actually OK?
>

You really don't have a clue on this. No tires will be wasted. Keep in
mind though, some damage is done and nothing will make it better, just
stop it from getting worse.

There is no way to eliminate the possibility it is the alignment unless
you have it checked. Definitely should be done before getting new tires
or putting the rear tires up front.

OTOH, I'd not be driving up and own steep twisting roads on $100 tires
either.

On Sat, 08 Jul 2017 12:55:24 -0400, > wrote:

> Take the word of a retired former Toyota Service Manager, who has also
> had experience in Rallye driving. The firstand simplest thing to do is
> AIR UP the tires by at least 5 PSI. The next SMART thing to do is get
> the alignment verified. When the tires need replacement replace with a
> heavier duty tire - an LT rated tire is recommended on that vehicle,
> and if it has the 265 65 tires on it, fo to 245 70 instead. Reducing
> the width of rubber on the road will reduce the instability of the
> tread on hard turns.
>
> It's not a race car - you don't need wide meats on it.

Thanks for the advice of harder pressure which I will certainly do!

I agree with you on the lack of need for width.

It has 225s on there now, which is the OEM tire.
Nothing wider than that is needed I agree.

The rest is looks but it's an SUV for heaven's sake so all that low-profile
stuff is for posers.

On Sat, 8 Jul 2017 13:22:11 -0400, Ed Pawlowski > wrote:

> I'd not be driving up and own steep twisting roads on $100 tires
> either.

Is that really a sound logical statement?

Here's my super simple logic.
* The tires meet all USA legal specs for the vehicle including exceeding
the load range (105S versus 102S).

You imply that a tire that meets or exceeds the specs for the car is
unsafe, just because I paid $100 for that tire (mounted & balanced).

Maybe I'm missing something critical but I can't find the logic in your
argument?

On Sat, 08 Jul 2017 13:01:58 -0400, > wrote:

> You can have an alignment CHECKED - if no adjustment is required,
> for a whole lot less than $100 if you get it to the right shop.

That's the HOLY GRAIL of services if it exists.

What would be perfect is a "free alignment check" and no charge if the
alignment doesn't need adjusting - but that may never happen for two
reasons.
* Alignment is a range (it's not just a single number), and,
* Nobody offers that anyway (that I can find).

Second-best (and perfectly acceptable) is a $25 alignment check-only, just
like I go to diagnostic-only smog stations, where all they do is MEASURE
the front toe and front camber (which is all that I need).

> Also, you do not need a "4 wheel" alighnment.

I've been reading up on alignment where the Toyota only has front
camber/caster (which is one setting) and toe, so that's all I need are
those two things.

If I can find a shop who will do those two CHECKS for around $25 that would
make logical sense.

But to pay for an entire mounted tire just to save on a mounted tire seems
like throwing good money away logically as it was aligned two years ago
(and at that time, it needed it because the front left was wearing really
fast).

Now they're wearing evenly.

> The toe in can be easily
> checked, even without a fancy alignment machine, by anyone worthy to
> call himself a mechanic. Less than half an hour's work either way if
> no adjustment is required.

I googled how to check toe and LOTS of people seem to be using string.
All I need is to tie a string to the center point and then cut the ends off
on each side at the center of the tire tread in front and in back at the
midpoint of the wheel axle.

That's a cost of four strings!

> Either way, I'd pay to MAKE SURE rather than take a chance on having
> to keep throwing tires at it.

I completely understand and agree that if EVERY tire was wearing unusually
fast (which is what happened two years ago to the left front tire), then a
$100 alignment makes perfect logical sense.

But to pay the cost of an entire 40,0000-mile tire just for a remote chance
of getting a thousand or two thousand miles out of the process seems like a
horrid cost:benefit ratio to me.

A $100 alignment is an entire $100 tire completely wasted (in terms of
opportunity cost) if the $100 alignment is not needed.

> That said - in YOUR SITUATION, the first thing I would do is check and
> verify tire pressures, and AIR UP 5 PSI.

Here's what I definitely will do given the really sound advice.
* Since I never check PSI, I'll start using 40psi (35 is normal)
* Next time I'll get stiffer sidewalls (105S instead of 102S)
* I will rotate every change of seasons (I cross hatch with no spare)
* I will take the downhills slower (if I can but I'm always the slowest)
* I will look for a $25 toe/camber-caster only check around town

To me, if a $25 toe/camber-caster only check existed, it would be a no
brainer. But to definitely throw away a perfectly good $100 40K-mile tire
in opportunity cost just to possibly save a couple thousand miles of wear
on two tires seems not like an obvious cost:benefit logical decision of a
$100 alignment.

On Sat, 08 Jul 2017 09:46:58 -0700, Bill Vanek >
wrote:

> At the same time, it would be nice to know that your front suspension
> and steering parts are not dangerously worn, and that should be
> checked in an alignment. But it's your car, your life, and your money,
> so do whatever you want. You've gotten solid advice here, you just
> have to make a decision.

I agree with you that the advice is "solid" here.
* It could be normal given the steep slow many curves, or,
* It could be both the camber and toe is too positive.

The only way to tell whether that's the case is to sink $100 into an
alignment.

I don't think it's at the level of "dangerously worn" though but you seem
to think so (but on what evidence?).

On Sat, 08 Jul 2017 13:02:50 -0400, "Steve W." > wrote:

>> Thank you for that advice of
>> * Downhill twisting causes more front end wear than uphills
>> * Rotate more often
>> * Stiffer sidewall might help
>> * (less positive) camber might help
>>
>> On the camber, if my search results are correct, the outside edge tire wear
>> would be due to too much positive camber (top spread out). That seems to
>> indicate that I would *lessen* the (positive) camber (get it closer to zero
>> than it is now).
>>
>> Is that the correct direction?
>
> Add some negative camber to move the tires closer in at the top,
> correct. That would place some extra weight on the inner edge of the
> tires and reduce the amount of wear at the outer edge.
>
>>
>> On the "stiffer sidewalls", I searched for what that means in terms of
>> beign able to actually choose the stiffer sidewall between two tires was
>> the aspect ratio and the load range.
>>
>> Is that correct?
>
> Correct. The higher the speed rating and the higher the load rating the
> more rubber and plies are in the sidewalls. That makes the sidewall
> stiffer. That will work to prevent the edges from trying to roll under
> causing the wear you are seeing. The drawback is that the stiffer tires
> reduce ride quality.
>
>>
>> I'm not likely to get a "shorter" tire aspect ratio so the only viable
>> option left is the higher load range (like going from 102S to 105S).
>>
>> Are you suggesting that a higher load range tire will have less outside
>> edge feathering?
>
> Yes. Raising the air pressure will also stiffen the tire, but it can
> cause issues of it's own.

That all sounds like in the right direction!
* higher air pressure to reduce "roll" (maybe 36psi to 41 psi)
* less positive camber & less positive caster to reduce feathering
* stiffer sidewalls (using higher load range numbers) than OEM
* less wide tread contact patch (it's got the OEM 225s on it now)

On Sun, 9 Jul 2017 05:51:14 +0000 (UTC), Chaya Eve
> wrote:

>On Sat, 08 Jul 2017 09:46:58 -0700, Bill Vanek >
>wrote:
>
>> At the same time, it would be nice to know that your front suspension
>> and steering parts are not dangerously worn, and that should be
>> checked in an alignment. But it's your car, your life, and your money,
>> so do whatever you want. You've gotten solid advice here, you just
>> have to make a decision.
>
>I agree with you that the advice is "solid" here.
>* It could be normal given the steep slow many curves, or,
>* It could be both the camber and toe is too positive.
>
>The only way to tell whether that's the case is to sink $100 into an
>alignment.
>
>I don't think it's at the level of "dangerously worn" though but you seem
>to think so (but on what evidence?).

No, I have no reason to think that. What I did say is that they are
ruined, and nothing can change that, even if they are still usable and
safe. If you rotate the tires, you'll just ruin the back tires, too.
The feathering itself does not make them dangerous, but they will
become noisy, if they aren't already.

On 9/07/2017 3:54 PM, Chaya Eve wrote:
> On Sat, 08 Jul 2017 13:02:50 -0400, "Steve W." > wrote:
>
>>> Thank you for that advice of
>>> * Downhill twisting causes more front end wear than uphills
>>> * Rotate more often
>>> * Stiffer sidewall might help
>>> * (less positive) camber might help
>>>
>>> On the camber, if my search results are correct, the outside edge tire wear
>>> would be due to too much positive camber (top spread out). That seems to
>>> indicate that I would *lessen* the (positive) camber (get it closer to zero
>>> than it is now).
>>>
>>> Is that the correct direction?
>>
>> Add some negative camber to move the tires closer in at the top,
>> correct. That would place some extra weight on the inner edge of the
>> tires and reduce the amount of wear at the outer edge.
>>
>>>
>>> On the "stiffer sidewalls", I searched for what that means in terms of
>>> beign able to actually choose the stiffer sidewall between two tires was
>>> the aspect ratio and the load range.
>>>
>>> Is that correct?
>>
>> Correct. The higher the speed rating and the higher the load rating the
>> more rubber and plies are in the sidewalls. That makes the sidewall
>> stiffer. That will work to prevent the edges from trying to roll under
>> causing the wear you are seeing. The drawback is that the stiffer tires
>> reduce ride quality.
>>
>>>
>>> I'm not likely to get a "shorter" tire aspect ratio so the only viable
>>> option left is the higher load range (like going from 102S to 105S).
>>>
>>> Are you suggesting that a higher load range tire will have less outside
>>> edge feathering?
>>
>> Yes. Raising the air pressure will also stiffen the tire, but it can
>> cause issues of it's own.
>
> That all sounds like in the right direction!
> * higher air pressure to reduce "roll" (maybe 36psi to 41 psi)
> * less positive camber & less positive caster to reduce feathering

Camber and caster give you stability at speed. Changing those outside
specs can lead to unintended consequences.
A small amount of positive camber at the front is normal. With no camber
possible at the rear due to a solid live axle, positive camber at the
front reduces cornering power at the front relative to the rear. This
will result in a slight *understeer* and this is good for straight line
stability. Reducing your camber angles at the front will likely result
in an oversteering car. This can be dangerous.
The caster angle creates self aligning torque. A reduction in caster
will make the car less stable.
The car steering geometry specs will have been designed to make your car
safe to drive in all circumstances. In effect, a compromise. If you want
to make changes to factory specs, you really need to know what you are
doing and have a clearly expressed goal. Steering geometry is at best a
compromise. A change for the better in one area may well make another
area more dangerous with regard to vehicle handling.

> * stiffer sidewalls (using higher load range numbers) than OEM
> * less wide tread contact patch (it's got the OEM 225s on it now)
>


--

Xeno

On 9/07/2017 3:51 PM, Chaya Eve wrote:
> On Sat, 8 Jul 2017 13:22:11 -0400, Ed Pawlowski > wrote:
>
>> I'd not be driving up and own steep twisting roads on $100 tires
>> either.
>
> Is that really a sound logical statement?
>
> Here's my super simple logic.
> * The tires meet all USA legal specs for the vehicle including exceeding
> the load range (105S versus 102S).
>
> You imply that a tire that meets or exceeds the specs for the car is
> unsafe, just because I paid $100 for that tire (mounted & balanced).
>
> Maybe I'm missing something critical but I can't find the logic in your
> argument?
>
The logic is *you get what you pay for*.

Cheap tyres do not perform as well as good quality tyres. I never buy
cheap tyres for my car(s). When the OEMs wear out, I usually fit
Michelins which I have found are not a great deal dearer than the OEM,
and in some cases cheaper, but they grip like baby**** on a blanket. To
me, grip on the road is a factor worth paying for. If you buy tyres on
price alone, you are doing yourself a disservice.

--

Xeno

On Sun, 9 Jul 2017 19:56:29 +1000, Xeno > wrote:

> The car steering geometry specs will have been designed to make your car
> safe to drive in all circumstances.

The specs are almost always a *range* so there's room to be at one end or
the other, isn't there?