Tires, The Wheels We Roll On

[smallpoxgirl]

Does anyone know, is there a reason that used tires can't be recycled? Seems like you could melt down the rubber and reuse it, and recycled the steel and reuse it. Maybe it doesn't work that way though.

[dohboi]

Generally with recyling of anything other than glass and maybe aluminum, the quality degrades with each recyling, so you can't make the same product. As far as I've heard, tires have been shredded and used in roads, but I haven't heard of them being made into new tires.

But that's just off the top of my head.

[pup55]

i

s there a reason that used tires can't be recycled

Most of the tires on these big earthmovers are retreaded and re-used several times.

Aircraft tires are also retreaded and recycled frequently at least once, sometimes more. There is rigorous testing of the tires to make sure they are safe.

Most truck tires (I am thinking the 18-wheelers now) are also retreaded and recycled, perhaps three or four times during their life, provided the carcass holds together.

Passenger tires are not recycled anymore, or perhaps I should say, were not recycled, because the imported passenger tires are so cheap (for the moment) that it is non-economical to do so.

Most of the tires that are not recycled are ground up in some way and used in landscaping or other low-tech products, or are burned in power plants as an energy source. Ground up tires makes pretty good fuel, except that it contains little pieces of metal, etc.

This whole industry should experience a renaissance once the flow of imports stops (which it will) and once the raw material costs skyrocket (which they are right now). In the immediate postwar period, 1945-1965 a pretty big industry developed in retreading, however, since the early 70's this industry contracted by about 75% when it became uneconomical to do the passenger tires.

Reprocessing of rubber in general is difficult because unlike plastic, when the tire or other rubber article is cured, a permanent chemical reaction happens which is irreversible. The most efficient way is to grind it into a fine powder, which can sometimes be used as a component of the same or some other formulation.

Don't ask me how I know all of this.

[bratticus]

Tire dealer mines rich vein (link)
By Mike McLean
Spokane Journal of Business
June 12, 2008

...“We didn’t do much sales in the U.S. last year,” he says. “We buy and send tires overseas.”...

...Servine says some brand new mining equipment is sitting on blocks for lack of tires.

“We have open orders with some customers,” he says. “If we find two tires for them, we buy them. If we find 12, we buy all 12, because we know we already have the customers.”...

[Tanada]

Speaking of Tires I am in need of a new set and have been doing a lot of boning up on the subject to balance fuel economy, bad weather/road conditions and tread life for my next set of tires. One of the things I have re-discovered is that higher pressure promotes greater fuel economy and then I had a startling thought. For many cars in the USA you can substitute LT (Light Truck) tires for P (Passenger car) of the same size. This would allow you to go from a typical tire pressure of 32 psi to 65 psi, which should give you a significant improvement in fuel mileage.

Have any of you done so and if so how much difference did you notice in comfort and handling vs improved fuel economy? Higher profile tires are inherently more efficient if properly inflated and LT tires start with an aspect ratio of 75, at least I have not seen any for sale below that ratio. The OEM tires on my wife's car are P195/60R15, the only LT tire assembly of the same size is the smallest available size without special order, the LT175/75R14. On the ground the two tires are only .3 inches (7.6 mm) different in circumference causing less than half a percent difference in speedometer accuracy. However it would mean buying an additional set of rimes for the car to minus size by 1. If the fuel economy improvement is enough it will be worth it, but I am hoping someone has real world experience to back up that belief. The OEM tires have a max inflation of 35 psi while the LT alternate tires are rated for 50 psi.

Another factor is the LT alternate set would be 20 mm narrower than the OEM set, which gives better traction in snow or muck and more resistance to hydroplaning when the tires are half through their tread lifetime because the vehicular weight is concentrated in a smaller footprint.

Thoughts or real world experience anyone?

[SeaGypsy]

I had a set of aircraft tyres rated to 120psi on my motorhome, which gave a noticeable bit of extra mileage. Drove around Australia a few times with a variety of tyres, these lasted the longest and gave easy streering (unpowered) as well. More than anything I found to improve mileage slowing down on the highway to about 45 to 50 MPH (70-80kmh) was the really big one. I was getting 8km/ litre- 20mpg out of a small diesel driving a 4.5 ton vehicle at these speeds on these tyres. I got them off an old airforce friend for nix.

[Tanada]

I had a set of aircraft tyres rated to 120psi on my motorhome, which gave a noticeable bit of extra mileage. Drove around Australia a few times with a variety of tyres, these lasted the longest and gave easy streering (unpowered) as well. More than anything I found to improve mileage slowing down on the highway to about 45 to 50 MPH (70-80kmh) was the really big one. I was getting 8km/ litre- 20mpg out of a small diesel driving a 4.5 ton vehicle at these speeds on these tyres. I got them off an old airforce friend for nix.

What was the designation of the aircraft tires you got from your friend? Wheel diameter, tread pattern, anything like that you know or might remember would be interesting too me.

[SeaGypsy]

They fit straight on an Isuzu 4.5 ton truck. They had a slightly elevated profile, about an extra inch in diameter to LT tyres and a straight flat tread. From memory they were 18 inch 24 ply.
Here is a site in Oz selling used aircraft tyres:

http://www.airecy.com.au/TyresList.html

The ratings blitz anything else on the market for strength, the straight tread is very efficient. You can get any size up to 22 inch wheel size.

I got about 50,000 km out of them with not a single flat ever, and that was driving on extremely rough roads about half that distance.

[Revi]

I noticed the last time I bought tires that the price had doubled since the last time I bought them. Ouch! I was wondering why. They told me that the Chinese were to blame, because they couldn't get tires from there or something. Who knows? I figure it's another thing that is getting more expensive. I always wonder how everyone else around here can afford such expensive tires. They all seem to be driving big trucks with big tires. They must not be paying the mortgage or something.

[SeaGypsy]

In much of SE Asia people run their tyres to the metal because they can't afford even retreads. Driving at night in Manila it's common to see sparks flying off worn out tyres, the police have given up enforcing laws about this.

[the48thronin]

The difference between low pr 24.5 tires and rims. and 1100 22.5 ( standard profile) is less than 2 pounds per tire. The air pressure ratings are the same 110 pounds in my class. The tread depth of a drive type tire is 31/32s of an inch new. Virgin tires last me 400,000 miles Then I can sell them for 75$ casing fee to a recapper who recaps them. If I have need I put them instead on my trailer.

I use the lowprofile 22.5s on my truck , My wife uses lp 24.5 Our mileage expectations (usable life of tire) are equal. Because of GEARING my truck gets maximum fuel mileage at 58 MPH and my wifes aerodynamic truck gets the same at 58 or 74 MPH but loses almost a mile a gallon to go only 65 MPH due to being out of the power curve on the motor between gears.

They are touting new low rolling resistance tires as 6 percent fuel savers, but it is a scam.

The LRR tires have only 19/32 tread depth when new and were tested against new 31/32 depth tires, over the life of a tire when the tread gets down in the 19/32 range you always see a slight increase in mileage, and when it gets down to 10/32 you see even more due to the loss of weight in the wheel/tire assembly you are turning. DUH!

Most drivers lower dual tires down to 100 PSI for a better ride and don't realize they are shaving 100,000 miles off the life of a tire and losing 10 percent of their fuel mileage.. But then most do not have that accurate a record keeping system anyway.

Truck tires in the USA can only be recapped if the carcasses are less than 4 years old by reputable recappers, my carcasses are at or beyond the 4 year mark before I take them off and replace them with new virgin tires. ( I take mine off at 5 to 7 32nds)

Trailer tires are even when new only 17/ 32s or less tread depth Typically they are 11/32. My drive tires with 400,000 miles on them usually go onto my trailer for 2 more years and are removed when they get down to the 3/32 area at which time most recappers will still accept them for trailer recapping but not all recappers due to carcass life span lmits.

ps I only purchase tires that have MADE IN USA on them... my friends who buy Chinese brands get less than 200,000 miles out of them.

[Tanada]

For those of us not driving trucks of either heavy or light variety there have to be trade offs for passenger car tires. Anyone have any data?

[the48thronin]

For those of us not driving trucks of either heavy or light variety there have to be trade offs for passenger car tires. Anyone have any data?

look at the tire side wall.. it will read somewhere MAXIMUM weight rating XXXX at XX pounds per square inch. Fill them with a very accurate tire gage when they have not been rolling for at least 2 hours and hopefully it is about 70 degrees outside to the number on the tire. This will probably be the best fuel mileage without shortening the tread life number for a car. if your car is front engine and especialy if it is front wheel drive also add 3 pounds more to the front tires.

Borrow ( or buy) one of those ifra-red thermomiters ( point and read type) drive 20 miles and read your tires. If one side is warmer than the other add 1 pound to the hot side the next time they are cold. ( probably the drivers side due to passenger load weight LOL). Drive at the speed your car goes into overdrive plus a little but ( 3 or 4 mph but no faster.) check out [url]http:airtabs.com[/url] depending on how aerodynamic your car already is, tests using rent a cars show good results from tabs on the hood and roof. ( I have them on truck and trailer).

[pup55]

For many cars in the USA you can substitute LT (Light Truck) tires for P (Passenger car) of the same size. This would allow you to go from a typical tire pressure of 32 psi to 65 psi, which should give you a significant improvement in fuel mileage

The reason light truck tires have higher pressure ratings is because they were made that way. They have construction differences, such as extra body plies, which will allow them to carry more weight. The higher pressure is so that the tires do not deform as much under heavy load conditions. You may also have discovered that they're much heavier than the similar size and shape passenger tires because of that. Any nominal benefit in fuel economy will be partially offset by the fact that the tire is heavier.

The components are also quite frequently compounded differently because of the differences in service conditions...particularly speed and load related, which are quite different for a truck than they would be for a car, and naturally much much different for aircraft. Truck tread compounds, for example, are almost all natural rubber which runs much cooler than synthetic rubber but gives much worse treadwear, when reasonably equally compounded. Aircraft tires are compounded to solve the problem of what happens when you are flying around in the hold of an aircraft at zero RPM and at low temperatures, and then 5 minutes later hit some hot rough runway in Dallas in the summer.... in other words, they have to withstand having the crap beaten out of them....They're also mostly natural rubber but compounded for higher tear strength, thank goodness.

Also, whether or not you see any improvement in fuel economy with a given set of tires is really heavily dependent on how you drive your car, and over what kind of surfaces. Those rolling resistance tests that they use for the UTQG system are done in a pristine laboratory with regular surfaces with a robot driver and not subject to chaotic conditions such as rain, which could really make a huge difference. Actually, that's not totally accurate. The road tests are done over known routes out in the middle of Texas using human drivers that are told what to do by computer, so it's the next best thing.

It is also quite likely that by putting a type of tire on your vehicle that was not designed for it can give you some surprises, such as reduced treadwear, or, as you have noted, different traction properties.

So your tires might be round, and black, with a hole in the middle, and be very nearly the same size as the manufacturer calls for, and you may indeed get better gas mileage, it is just as likely that you will sacrifice in some other area of performance, and if you have not noticed that, it might very well mean that you never will, all the better, you will be just fine.... but I would not go out of the way to put LT tires on my car to save fuel because a lot of times they're more expensive anyway.

[vtsnowedin]

A lot of good points in the above posts. I would add only that the tires for a car a designed with a certain amount of flex in the sidewalls. This comes into play when you need to make a sudden lane shift at speed. In testing they call it a J turn. A deer jumps into the lane your in. you yank the wheel to the left then back to the right. How well the car responds to this depends on a lot of things between the road and the frame with the tires being one of them. The longer the full width of the tread pattern is in contact with the road and not skidding the more control you will have. Switching to stiffer sidewall tires will reduce this time and make your car less responsive. Saving a little gas will seem silly if you roll your car or run off the road into a ledge because you started skidding twenty feet sooner then you would have with the right tires for the car.

[pup55]

Saving a little gas will seem silly if you roll your car or run off the road into a ledge because you started skidding twenty feet sooner then you would have with the right tires for the car.

I guess I would throw out just one more piece of useless information, which is to remind you of what happened a few years ago in the Ford Explorer case....

Those vehicles were top-heavy, as you may recall, and the vehicle manufacturer found out that the problem of potential rollover could be partly solved by running the tires at lower inflation pressure, reducing the tire height slightly. The tire manufacturer just hated this, because those tires were designed to run at higher pressures, for just the exact sidewall deformation issue that vtsnowedin mentioned. They strongly recommended a slightly different size tire.... of course this would have cost an extra few dollars per vehicle, and the vehicle manufacturer resisted... money talks.

So the tires ran hot, a lot of them blew out, maimed and killed a lot of people and the lawsuits started to fly. Ultimately the tire company caught the bulk of the crap...ended up closing down a tire plant, putting a lot of people out of work, and recalling a lot of tires....when that wasn't the real problem.....

So if you are the proverbial little old lady in Pasadena who drives safely, under non-extreme conditions, and maintain your vehicle, statistically the odds of you having any problems are close enough to zero that you do not even think of it. But from the standpoint of the tire company, if they produce 20 million tires, they well know that some of them are going to end up on an overloaded SUV trying to pass a truck in Arizona in July, and so their engineering decision, which has to be money driven as well as engineering driven, has to take into account the usage that is clear out on the little tail of the bell curve.....and decisions you the consumer make can pretty easily move the chance of failure a little bit closer to the middle of the bell curve....

Just something to think about. The manufacturers of anything dangerous well know that some percentage of their product is going to end up being used clear on the end of the bell curve.... chain saws, for example.... lawnmowers..... and it's a hard job anticipating what some consumer will do at some point a couple of years down the road.....

[Revi]

Tires are expensive. There are a lot of people around here with $200 tires. That means when they wear out the driver needs to cough up $800. Remember retreads? It may be time to figure out some other cheaper, but still safe kind of tire in order to keep our cars running.

[pup55]

I keep thinking there will be a renaissance in that business at some point... Back in the stone age, a retreaded passenger tire would sell for about 1/3 the amount of an original one.... so you figure that for a 200 dollar tire, some schmoe might pay 65 or so to get a retread, and the cost to do the retreading is sufficiently low that there could be a little business there....

The thing that killed it was the imports, obviously. On some of the low end vehicles it's still possible to get a chinese tire for 75 or so, and at 25 dollars a tire it's practically impossible to recover the casing, pay for the tread rubber, do the actual retreading and redistribute it to the customer for that....

Plus it's nasty work.

Truck tires work, though, I think the new ones were about 400 dollars, last I checked, and you could get a retread for about 100-120 so that starts to work economically....especially if you can retread the same casings 3 or 4 times...

You're always going to have the stigma of the old days, when a lot of people were in that business who had no idea what the hell they were doing.... but in a world of no interstate highways, annual vehicle travel being under 5000 miles per year, and low speeds, the performance issues were manageable.

Nowadays, your friend is going to expect to drive those high performance retreads at the same 110 mph that he would the OE tires, without fear of failure, and at the same ride quality as the original tires.... that's the hard part.... people are more tuned into ride quality than they ever were back in the dinosaur era....at least for the time being.

[vtsnowedin]

Tires are expensive. There are a lot of people around here with $200 tires. That means when they wear out the driver needs to cough up $800. Remember retreads? It may be time to figure out some other cheaper, but still safe kind of tire in order to keep our cars running.

Been there ,done that ,and will not go back to recaps.
Even if that $800 dollar set of tires only lasts 40,000 miles that is just two cents per mile. With a twenty mile per gallon rig and $3.30 gas your already up to 16.5 cents per mile.Keep your tires inflated properly and they will probably save you enough gas to pay for their replacements.
Hey Revi, what tires do you run on your wife's car in Maine winters?

[the48thronin]

Truck tires 22.5 low profile.. if you buy 8 at a time you can get them in a lug tread from a cheap brand at 3200 ( price includes them giving you $75 dollar trade in or you pay more.

The brand I buy ( Kelly made in USA ) 8 new drive tires 4,000 dollars includes 45$ trade in for a recappable casing) or you pay more.

Accutrac recaps made in Kentucky , (they will only cap bridgstone or michelin casings) $280 each casing must be less than 4 years old and only certan steer tire casing accepted.

low budget USED tires any brand your risk 5/32 tread at a truck stop $300 used recaps same stipulations same tread depth $250.

The chances of capping a casing more than once... zilch!

The chances you can save money buying cheap tires or recaps....NONE!

IF you have a mega fleet and own your own recapper... you can pretend to save money and hold out hoping they pass cap and trade. Sell your carbon credits from recapping maybe?


Back to reality 400,000 miles from 8 drive tires ( half will last more than that but none will make 500,000 most likely. You will also use 4 steer tires and have all of them suitable for trailer mounting, you will only get 45$ for the casings on the drive tires and 50% of them will have been rplaced between 300 and 400 thousand anyway. The chances you can wear all 8 tires out at once....NONE!

Why do they sell used tires and recaps at truck stops.. because fleets hire people they do not know including a certain number of thieves. You see fleet drivers carrying home the flat/blown tire to prove they didn't sell it. The fleet buys anything that will get their truck/trailer to their own shop and then they put on tires and sell the used ones locally and they make thier way back to the used tire rack at the nearest TS or to a capper.