Odd wear polished edges

Joined
Jan 12, 2008
Messages
499
Location
Long Island, NY
I have not seen wear like this before. The edges are are actually shiny polished.

The story to go with them. These are on the back of my neighbors 2019 Toyota 4Runner. I checked the air pressure and they were at 44 psi, door sticker calls for 32 psi. Further investigation one has a 2015 date code the other has 2016. She said she just got them from the used tire place to replace the totally worn ones she had and needed repair from screws. She said she only drove about 2 miles on them. I adjusted pressure back to 35psi for now as it was warmer outside but getting colder.

So at this point I don't know what they were originally on or how long they sat at used tire place. I know there is at least one plug, rubber is cracking between tread and they are at age to be replaced. They have 2x the tread as her front tires that also need replacement. I don't know finances and what she might be willing to spend for 4 new or 4 used with newer date codes that are available on CL and FB marketplace.

tire1.jpg

tire2.jpg

tire3.jpg
 
Joined
Sep 29, 2009
Messages
3,007
Location
Deep in the heart of Jersey
That kind of wear happens when you set the pressure to what is on the door frame. That pressure is for the tires which came with the car. These tires obviously are a different model. Bump them up to 40psi, and the tires will have a better feel when cornering, and probably up the gas mileage a bit. When over-inflated, the center of the tire wears more. When under-inflated, the outside of the tire wears more.,,,
 
Joined
Aug 20, 2003
Messages
18,963
Location
NE,Ohio
That kind of wear happens when you set the pressure to what is on the door frame. That pressure is for the tires which came with the car. These tires obviously are a different model. Bump them up to 40psi, and the tires will have a better feel when cornering, and probably up the gas mileage a bit. When over-inflated, the center of the tire wears more. When under-inflated, the outside of the tire wears more.,,,
Couldnt agree with much you said there.
 
Joined
Feb 22, 2003
Messages
4,293
Location
Somewhere in the US
I have not seen wear like this before. The edges are are actually shiny polished.

The story to go with them. These are on the back of my neighbors 2019 Toyota 4Runner. I checked the air pressure and they were at 44 psi, door sticker calls for 32 psi. Further investigation one has a 2015 date code the other has 2016. She said she just got them from the used tire place to replace the totally worn ones she had and needed repair from screws. She said she only drove about 2 miles on them. I adjusted pressure back to 35psi for now as it was warmer outside but getting colder.

So at this point I don't know what they were originally on or how long they sat at used tire place. I know there is at least one plug, rubber is cracking between tread and they are at age to be replaced. They have 2x the tread as her front tires that also need replacement. I don't know finances and what she might be willing to spend for 4 new or 4 used with newer date codes that are available on CL and FB marketplace.

[[Photos omitted]]

We know almost nothing about these tires. Whatever inflation pressure was put in the tires at the used tire place - about 2 miles ago - hasn't had enough miles to make a difference.

Best Guess: These were from a lightly used vehicle, which did point to point delivery, rather than within the city. The edges weren't used much, so they polished from the straight ahead driving.
 
Joined
Feb 22, 2003
Messages
4,293
Location
Somewhere in the US
That kind of wear happens when you set the pressure to what is on the door frame. That pressure is for the tires which came with the car. These tires obviously are a different model. Bump them up to 40psi, and the tires will have a better feel when cornering, and probably up the gas mileage a bit. When over-inflated, the center of the tire wears more. When under-inflated, the outside of the tire wears more.,,,
Ah ..... Mmmm ...... Not exactly

Tires are standardized and it is a common misconception that the placard inflation pressure only applies to the original tires. It does not. It applies regardless of who makes the tire.
 
Joined
Sep 29, 2009
Messages
3,007
Location
Deep in the heart of Jersey
Ah ..... Mmmm ...... Not exactly

Tires are standardized and it is a common misconception that the placard inflation pressure only applies to the original tires. It does not. It applies regardless of who makes the tire.
Ah, you guys need to realize that what was used in the past, is not the same as of right now. And the pressure of the factory tires has changed as to whats available TODAY. Go ahead and check the tires for yourself. If TODAY'S tire's require those same pressurizes, why do the Tires made today have higher rating?. If you like replacing tires due to uneven wear, or poor handling, run the pressure some outdated sticker on your car says to. Most newer tires will appear low or even flat with 32 psi in them, and handle like it to.,,,
 
Joined
Feb 22, 2003
Messages
4,293
Location
Somewhere in the US
Ah, you guys need to realize that what was used in the past, is not the same as of right now. And the pressure of the factory tires has changed as to whats available TODAY. Go ahead and check the tires for yourself. If TODAY'S tire's require those same pressurizes, why do the Tires made today have higher rating?. If you like replacing tires due to uneven wear, or poor handling, run the pressure some outdated sticker on your car says to. Most newer tires will appear low or even flat with 32 psi in them, and handle like it to.,,,
Ah ..... Mmmm ..... I'm not sure what you are saying, but if it is what I think, you are wrong.

First, allow me to interpret what I think you are saying: That the max pressure written on the sidewall of passenger car tires has changed and that means that the tire is different.

Nope. While it may be true that the max pressure has changed (or may be it hasn't!), the load table for a given size has not. The 2022 table is the same as the - say - 1982 table. Now that doesn't mean the tires have stayed the same over time - surely that is not the case. But it does mean that the inflation pressure specified on the vehicle tire placard is referencing a load table which has not changed over time.

I go into more detail here: Barry's Tire Tech: Load Tables

Pay particular attention about half way down where I talk about "The notes on page 1-34". Those notes say that the max pressure can be 35, 44 or 51 psi, but the load table is still the same for each. If you want, I can publish the load table from 1989, which is the earliest Tire and Rim Yearbook I have. The latest one I have in paper form (not digital) is from 2020. Let me assure you they are the same.
 
Joined
May 25, 2005
Messages
2,500
Location
USA
Cupping. Looks like fairly severe wear. I'm still suprised that people can buy used tires. Colorado has made it against the law to sell used tires.
 
Joined
Sep 29, 2009
Messages
3,007
Location
Deep in the heart of Jersey
Ok MR. Engineer if your the "Expert" here, how come in 2022, the tires made today don't all have the max pressures listed as 32 PSI ? And wouldn't the rolling resistance be less if the pressure was increased by just 8 pounds, from 32 to 40?. If you don't think it does, please tell the world why it wouldn't. By allowing the vehicle to roll / move down any given road easier, wouldn't it get a bit more gas mileage ?. And run cooler? I'm sure the people that make cars are looking for any means to up the mileage in their vehicles for little to no added mfg cost on their part. Having a higher weight bearing capacity and longer tire life is just the side benefit of upping the tire pressure. And as we all know, tires that are low on pressure are more likely to blow out. Riding down the highway at 70 mph on a 90 degree day with a tire low on air, is a blowout waiting to happen. That's what use to happened all the time when tires had low fill pressure years ago. If you think I'm wrong, let 10 lbs out of all your tires and kep m that way for 6 months. Then come back and tell how it effected your handling, mileage, and overall look of you tires.,,
 
Joined
Sep 29, 2009
Messages
3,007
Location
Deep in the heart of Jersey
Ah ..... Mmmm ..... I'm not sure what you are saying, but if it is what I think, you are wrong.

First, allow me to interpret what I think you are saying: That the max pressure written on the sidewall of passenger car tires has changed and that means that the tire is different.

Nope. While it may be true that the max pressure has changed (or may be it hasn't!), the load table for a given size has not. The 2022 table is the same as the - say - 1982 table. Now that doesn't mean the tires have stayed the same over time - surely that is not the case. But it does mean that the inflation pressure specified on the vehicle tire placard is referencing a load table which has not changed over time.

I go into more detail here: Barry's Tire Tech: Load Tables

Pay particular attention about half way down where I talk about "The notes on page 1-34". Those notes say that the max pressure can be 35, 44 or 51 psi, but the load table is still the same for each. If you want, I can publish the load table from 1989, which is the earliest Tire and Rim Yearbook I have. The latest one I have in paper form (not digital) is from 2020. Let me assure you they are the same.
What I post on here is my own personal experience from over 50 years of driving and vehicle maintenance. I've tried alot of different combinations and what I said, works for me. If you believe what someone else believes, go for it. But, only make comments after you have tried it first hand. Back in the day if a tire said the max pressure was 32 PSI, that's what I put in. Over-inflating a tire came at a cost. Premature wear. So I didn't do it. Nowadays tire can go up to 51 psi. I wouldn't run car tires that high , but knowing they can go up some, I experimented. It's amazing how much better your car can handle and feel on the road. with just subtle changes. After all the "engineers" that made your car won't know what type roads you drive on, or how you load it , or don't load up your car. Whether you tow a boat or a travel trailer, or a race car around thru the mountains. So you have to figure out what works best. That means adjusting tire pressures to what gives the best feel and handling. That's what I've done. But if your vehicle feels sluggish going around corners, and you can hear what sound like the tire is being dragged around corners against it's will, Even if it's filled to what Barry's book claims to be the optimum pressure, adding air to them will make a world of difference. My goals have been to get the best handling and longest life out of my tires. I do what works for me, you and Barry can do what you want.,,
 
Joined
Feb 22, 2003
Messages
4,293
Location
Somewhere in the US
OK, let's keep our eyes on the prize. This brouhaha is over this statement:

...... That pressure is for the tires which came with the car. These tires obviously are a different model. .......,

Before I address that, allow me to answer a question that has been posed:

....... how come in 2022, the tires made today don't all have the max pressures listed as 32 PSI ?........

Because they are a different type of tire than the era you are referring to.

In the era you are referring to, they didn't list a max pressure on the sidewall of tires. Prior to the adoption of FMVSS 109 (in the early 1970's), there was no requirement at all. Nothing was listed on the sidewall regarding max load or max pressure.

When FMVSS 109 was adopted, the first tires had load tables that ended at 32 psi (nowadays that pressure is 35 psi). The most common types were "Super Low Section" and "AlphaNumeric". I've published the load tables here: Barry's Tire Tech: Vintage Tire Exchange

- AND - the tires didn't have the max pressure listed on the sidewall. What they had was this: " Max Load XXXX at 32 pai". Notice, no max pressure. Only a relationship. As required by the new law FMVSS 109.

When P metric tires were introduced in the late 1970's, they had a different load table - and it ended at 35 psi. They also came in the form "Max Load XXXX at 35 psi" Again, no max pressure.

It wasn't very long before Speed Ratings were introduced and that complicated things. H speed rated tires had the same load table, but they were supposed to be inflated higher for those higher speeds. So tire manufacturers changed the way they expressed the max load thing to "Max Load XXXX, Max Pressure YY. Notice that the "at" is gone.

Nowadays, you will find tire manufacturers using both forms. I'm not sure why each chooses to do what they do.

So back to the original contention - that the vehicle tire placard only applies to the original tires that came on the vehicle from the factory.

The placard is all about load carrying capacity. Not how the vehicle feels or how it performs. There is a HUGE!! range in how tires of the same size and inflated to the same pressure will perform - and that means grip, wear, fuel consumption, handling, etc.

Ya' see, the placard is referring to the load table - and the load table is the same for a given size regardless of who makes the tire. Yes, there will be differences in how the vehicle performs with different tires on it, but tire manufacturers also have to deal with the load table. So if a tire performs differently, it's because the tire was designed to perform differently, and that is independent of the inflation pressure, not that the inflation pressure on the placard doesn't apply. If one wants to use a different pressure in order to change the way their tire feels or performs, go for it. But be aware that the load table still applies - as does the vehicle tire placard. don't go below the placard pressure or you run the risk of an underinflated tire failure.
 
Last edited:

Sequoiasoon

Thread starter
Joined
Jan 12, 2008
Messages
499
Location
Long Island, NY
Pic 2 looks like a nail? Unless thats the plug?
It's a plug, I saw that also but poked with a small screwdriver and it's rubber. I think it might be a plug/patch thing. The cracking around it is also concerning.
We know almost nothing about these tires. Whatever inflation pressure was put in the tires at the used tire place - about 2 miles ago - hasn't had enough miles to make a difference.

Best Guess: These were from a lightly used vehicle, which did point to point delivery, rather than within the city. The edges weren't used much, so they polished from the straight ahead driving.
Just something I have never seen like that. In person they are very shiny. I've personally put over 200k on 5 different vehicles and 150k+ on 7 others. Unknown number of regular and snow tires between them. Never shiny edges.
 
Joined
Sep 23, 2006
Messages
538
Location
757 Virginia, USA
It's a plug, I saw that also but poked with a small screwdriver and it's rubber. I think it might be a plug/patch thing. The cracking around it is also concerning.

Just something I have never seen like that. In person they are very shiny. I've personally put over 200k on 5 different vehicles and 150k+ on 7 others. Unknown number of regular and snow tires between them. Never shiny edges.
I think they are shiny because the used tire store likely put high gloss tire dressing on the tire to improve the appearance of the used tires. Because they were overinflated to 44 psi and your friend only drove 2 miles from the store, the edges of the tires never got scrubbed like the middle portion of the tread.
 

Sequoiasoon

Thread starter
Joined
Jan 12, 2008
Messages
499
Location
Long Island, NY
I think they are shiny because the used tire store likely put high gloss tire dressing on the tire to improve the appearance of the used tires. Because they were overinflated to 44 psi and your friend only drove 2 miles from the store, the edges of the tires never got scrubbed like the middle portion of the tread.
But the sidewalls are not polished and shined up or the edges of the blocks, also not shiny between them anywhere. I don't know many that would put tire dressing on the tread. I have seen it on Craigslist on some. I cringe at the thought of putting slippery stuff on the treads.
 

OVERKILL

$100 Site Donor 2021
Joined
Apr 28, 2008
Messages
53,897
Location
Ontario, Canada
Over inflated, edges did have as much contact.
Yup, my take is the same, edges barely contacted the road (or didn't contact the road) in the 2 mile drive home due to over-inflation and they've been sitting a while, so they have developed a "shine" to them due to oxidation and other aspects of the aging process. I'm sure we've all seen shiny trailer tires on trailers that have miles on them, but haven't moved in years, IMHO, same thing we are seeing here.
 
Joined
Mar 3, 2011
Messages
2,824
Location
California's Central Coast Wine Country
Ya' see, the placard is referring to the load table - and the load table is the same for a given size regardless of who makes the tire. Yes, there will be differences in how the vehicle performs with different tires on it, but tire manufacturers also have to deal with the load table. So if a tire performs differently, it's because the tire was designed to perform differently, and that is independent of the inflation pressure, not that the inflation pressure on the placard doesn't apply. If one wants to use a different pressure in order to change the way their tire feels or performs, go for it. But be aware that the load table still applies - as does the vehicle tire placard. don't go below the placard pressure or you run the risk of an underinflated tire failure.
An outstanding public service announcement! Excellent!

Scott
 
Top