Outside edge of front tires stairstepping

Is it normal for the outside edges of the front tires to be stairstepping
on the outer inch or two only?

By stairstepping, I mean that you can't see the wear all that much but if
you rub your hand over the tread in one direction, you can feel a lip on
each side swipe tread.

If you run your hand over in the other direction, you don't feel it. You
only feel it if you run your hand from back to front on the outside tread
of the two front tires.

If you do the same with the rear tires or on the inner edge of the front
tires, you don't feel any 'stairstepping".

The tires are about a year old and are wearing the front outside edges
only.

Chaya Eve wrote:
> Is it normal for the outside edges of the front tires to be stairstepping
> on the outer inch or two only?
>
> By stairstepping, I mean that you can't see the wear all that much but if
> you rub your hand over the tread in one direction, you can feel a lip on
> each side swipe tread.
>
> If you run your hand over in the other direction, you don't feel it. You
> only feel it if you run your hand from back to front on the outside tread
> of the two front tires.
>
> If you do the same with the rear tires or on the inner edge of the front
> tires, you don't feel any 'stairstepping".
>
> The tires are about a year old and are wearing the front outside edges
> only.

What you feel is known as feathering, one side of the tread block wears
more than the other. If you looked at the end of the block it would
appear as a wedge.

It is commonly caused by improper toe settings and if on one edge only
by improper camber angle as well. BUT it can also be caused by using a
common tire on a vehicle that is driven aggressively. IE high speed
cornering. That places a lot of weight on the outer edge of the tire and
tries to force it to roll under. That will wear the outer edges rapidly.

Now if you had one spot that was "normal" then a wear spot then "normal"
going all the way around the tire that would be cupping. That is
normally a suspension wear problem.


--
Steve W.

On Wednesday, July 5, 2017 at 7:15:12 PM UTC-10, Chaya Eve wrote:
> Is it normal for the outside edges of the front tires to be stairstepping
> on the outer inch or two only?
>
> By stairstepping, I mean that you can't see the wear all that much but if
> you rub your hand over the tread in one direction, you can feel a lip on
> each side swipe tread.
>
> If you run your hand over in the other direction, you don't feel it. You
> only feel it if you run your hand from back to front on the outside tread
> of the two front tires.
>
> If you do the same with the rear tires or on the inner edge of the front
> tires, you don't feel any 'stairstepping".
>
> The tires are about a year old and are wearing the front outside edges
> only.

Your toe-in should be adjusted. Your tires have negative toe or your suspension is loosey-goosey.

On Thu, 06 Jul 2017 02:08:04 -0400, "Steve W." > wrote:

> What you feel is known as feathering, one side of the tread block wears
> more than the other. If you looked at the end of the block it would
> appear as a wedge.
>
> It is commonly caused by improper toe settings and if on one edge only
> by improper camber angle as well. BUT it can also be caused by using a
> common tire on a vehicle that is driven aggressively. IE high speed
> cornering. That places a lot of weight on the outer edge of the tire and
> tries to force it to roll under. That will wear the outer edges rapidly.
>
> Now if you had one spot that was "normal" then a wear spot then "normal"
> going all the way around the tire that would be cupping. That is
> normally a suspension wear problem.

That was a far better answer than I had expected so I appreciate your
expertise. The vehicle was aligned but probably about 2 years ago (while
the tires are about a year old).

The car is driven on a five mile hill every day with scores of hairpins but
it's NEVER driven fast. Those turns are made probably at 20 to 25 MPH (you
can't take the turns any faster and stay on your side of the road).

Could that steep (10% or so) continuously twisting 5-miles each way every
day have caused the "feathering" you explained my "stairstepping" to be?

On 7/6/17 3:15 AM, Chaya Eve wrote:
> On Thu, 06 Jul 2017 02:08:04 -0400, "Steve W." > wrote:
>
>> What you feel is known as feathering, one side of the tread block wears
>> more than the other. If you looked at the end of the block it would
>> appear as a wedge.
>>
>> It is commonly caused by improper toe settings and if on one edge only
>> by improper camber angle as well. BUT it can also be caused by using a
>> common tire on a vehicle that is driven aggressively. IE high speed
>> cornering. That places a lot of weight on the outer edge of the tire and
>> tries to force it to roll under. That will wear the outer edges rapidly.
>>
>> Now if you had one spot that was "normal" then a wear spot then "normal"
>> going all the way around the tire that would be cupping. That is
>> normally a suspension wear problem.
>
> That was a far better answer than I had expected so I appreciate your
> expertise. The vehicle was aligned but probably about 2 years ago (while
> the tires are about a year old).
>
> The car is driven on a five mile hill every day with scores of hairpins but
> it's NEVER driven fast. Those turns are made probably at 20 to 25 MPH (you
> can't take the turns any faster and stay on your side of the road).
>
> Could that steep (10% or so) continuously twisting 5-miles each way every
> day have caused the "feathering" you explained my "stairstepping" to be?
>

Bet you a dollar that if you took your ride into a good repair shop,
they'd find that your alignment is out of spec...

--
Don't cling to a mistake just because you spent a lot of time or money
making it.

On 7/6/2017 1:15 AM, Chaya Eve wrote:
> Is it normal for the outside edges of the front tires to be stairstepping
> on the outer inch or two only?
>
> By stairstepping, I mean that you can't see the wear all that much but if
> you rub your hand over the tread in one direction, you can feel a lip on
> each side swipe tread.
>
> If you run your hand over in the other direction, you don't feel it. You
> only feel it if you run your hand from back to front on the outside tread
> of the two front tires.
>
> If you do the same with the rear tires or on the inner edge of the front
> tires, you don't feel any 'stairstepping".
>
> The tires are about a year old and are wearing the front outside edges
> only.
>

Does not sound normal to me. Could be the toe-in is not adjusted
properly. How many miles on the car? Every checked the alignment?

On Thu, 6 Jul 2017 09:13:13 -0400, Ed Pawlowski > wrote:

> Does not sound normal to me. Could be the toe-in is not adjusted
> properly. How many miles on the car? Every checked the alignment?

If it were only the tires tilted inward at the front (toe) the whole tread
would be "feathered" would it not? This only has the outside edge of both
front tires feathered. So it can't be "just" toe.

I don't see how the miles matter but it has about 60K miles. Miles would
have nothing to do with this other than suspension wear but nobody is
suggesting suspension wear based on the evidence (for example, no cupping).

The alignment was last done about two years ago.
The tires are about a year old.

My take on this is that it's either "normal" for a car that is driven by
necessity (slowly) on twisty steep (10%) mountain roads for 10 miles (5
each way) every day, or there is something wrong.

It's not going to be a single thing since the entire width of the tread is
not feathered (only the outside edges) and since it's both front tires,
it's not obvious that it's something worn or out of alignment.

On Thu, 6 Jul 2017 09:02:16 -0400, Wade Garrett > wrote:

> Bet you a dollar that if you took your ride into a good repair shop,
> they'd find that your alignment is out of spec...

If it is the alignment, do you concur that it's a combination of the front
camber (tilted out too high at the top) and toe (turned inward too much at
the front).

The tires are "feathered" only on the outside edge of the tread (last inch
or two) evenly on both tires, but only on the front.

On 6/07/2017 5:15 PM, Chaya Eve wrote:
> On Thu, 06 Jul 2017 02:08:04 -0400, "Steve W." > wrote:
>
>> What you feel is known as feathering, one side of the tread block wears
>> more than the other. If you looked at the end of the block it would
>> appear as a wedge.
>>
>> It is commonly caused by improper toe settings and if on one edge only
>> by improper camber angle as well. BUT it can also be caused by using a
>> common tire on a vehicle that is driven aggressively. IE high speed
>> cornering. That places a lot of weight on the outer edge of the tire and
>> tries to force it to roll under. That will wear the outer edges rapidly.
>>
>> Now if you had one spot that was "normal" then a wear spot then "normal"
>> going all the way around the tire that would be cupping. That is
>> normally a suspension wear problem.
>
> That was a far better answer than I had expected so I appreciate your
> expertise. The vehicle was aligned but probably about 2 years ago (while
> the tires are about a year old).
>
> The car is driven on a five mile hill every day with scores of hairpins but
> it's NEVER driven fast. Those turns are made probably at 20 to 25 MPH (you
> can't take the turns any faster and stay on your side of the road).

That means you *are* traveling very fast, at least for the conditions.
What you are saying is that you are leaving no safety margin on each
hairpin. You will definitely be wearing the outer edges of the tyres
doing that.
>
> Could that steep (10% or so) continuously twisting 5-miles each way every
> day have caused the "feathering" you explained my "stairstepping" to be?
>
The hairpins are the reason for the feathering on the outer edges of the
tread. If you adjust to eliminate the feathering on curves, you may see
wear on the inside of the tread instead. It is a suspension geometry
anomaly, a compromise if you will, that you can do little about. If you
only drove on a freeway every day, you would see no feathering. FWD
vehicles tend to fare worse for a number of reasons, one being the
greater SAI angles generally used on them, another being the greater
weight on the steering axles. I get the same issue here with my Toyota
due to the predominance of roundabouts and sharp corners I need to
negotiate. The steering alignment was, and is, spot on.

Toe specs are usually given as a range. Set yours to the favourable side
of the spec range realising that FWD vehicles tend to be positive toe
rather than negative.

--

Xeno

On 7/6/17 9:26 AM, Chaya Eve wrote:
> On Thu, 6 Jul 2017 09:02:16 -0400, Wade Garrett > wrote:
>
>> Bet you a dollar that if you took your ride into a good repair shop,
>> they'd find that your alignment is out of spec...
>
> If it is the alignment, do you concur that it's a combination of the front
> camber (tilted out too high at the top) and toe (turned inward too much at
> the front).
>
> The tires are "feathered" only on the outside edge of the tread (last inch
> or two) evenly on both tires, but only on the front.
>

Above my pay grade.

For anything other than the over-inflation wear pattern (center tread
wear) I take it in for an alignment.

--
A good plan violently executed right now is far better than a perfect
plan executed next week.
- Gen. George S. Patton