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Hey, I’m Jeremy from 1A Auto. This is a tire.
Today I’m going to teach you about what all the numbers and letters on the side mean. One of the cool things about tires is that
the side of the tire actually tells you everything about the tire. One of the things that I find
really interesting is that the tire actually tells you how old it is. It tells you the
month it was made and the year it was made. This is really useful if you’re buying a used
set of tires from a junkyard or Craig’s List or eBay or something like that. Even if you’re
just buying them brand new at a store you can find out how old the tire actually is,
because sometimes you buy a brand new tire but you find out the tire is actually a couple
of years old. You always got to watch out for that at any place that you’re getting
a really good deal on tires. It may be an old tire. The way that you figure this out is, on the
side of the tire, there’s an oval with some numbers in it. If the tire was made before
the year 2000, it’s a three-digit number. It’ll be the week of the year that it was
made and then the year that it was made. In this case it would be the 16th week of the
seventh year. This could actually mean 1987 or 1997. In 2000, the number was actually
standardized because tires were getting confused between decades. Tire manufacturers started
using four-digit codes. Now it’s the 16th week of the seventh year and you can tell
it’s 2007. There’s no longer any confusion of 1987 or ’97. It’s 2007 because it’s 07.
This is, again, really useful if you’re buying a used set of tires. I’ve used it a bunch
of times and I’ve often been shocked at what I’ve found. On an actual tire you can see the number right
here. You can see it says 1607. If this was made in 2009, it would say the week it was
made, in this case 16, and then it would say 09 instead of 07. If it was a different week
of the year, it could say maybe 32 of 07. It’s always the first two digits are the week
and the second two digits are the year. One of the most important things about a tire
is the tire size. In this case we have 235/45/17. Two-thirty-five is the amount of millimeters
wide the tire is. The more millimeters, the wider the tire. The less millimeters, the
thinner the tire. Forty-five is the height of the sidewall. In this case it’s 45 percent
of 235. This is always a percentage of the width. Seventeen is the diameter of the wheel
itself. In this case it’s a 17-inch wheel. We have a 235 wide; 45 percent of 235 is the
height of the sidewall on a 17-inch wheel. On the tire itself, you can see the size of
the tire right here: 235 millimeters; 45 percent of 235 is the height of the sidewall. R actually
stands for radial; it’s a radial tire. Pretty much all tires these days are radials, and
17 is the diameter of the wheel. So: 235/45/R/17. Another really important factor about tires
is the load rating, the speed rating and the type of tire that it is. Today we have a 94Q
M+S. That’s what the side of the tire says. Ninety-four is the load rating. That means
it can handle 1,477 pounds all on that one tire. You multiply that times four and hopefully
your car weighs less than that. If it weighs more than that, you’re overloading your tires
and it’s unsafe. Q is the speed rating. That means these tires can go 100 miles an hour
safely. The higher the letter, the faster that you can go. You’ll see something like
a Corvette might have a Z-rated tire on it. Obviously this is pretty important if you
ever take your car to the racetrack or anything like that. You want to make sure your tires
are safe to go the speed that you’re going to be going. M and S. That is mud and snow.
That’s what most tires are. If you go look at your car right now, it probably has an
M and S on the side of it. It’s pretty much a good all season tire. You can buy strictly
winter tires or strictly summer tires or strictly race tires, but M and S is the pretty standard
all season tire. Right here next to the tire size, you get
your 235/45/R/17, you can see there’s an 94QM+S. That’s the 94 load rating of 1,477 pounds.
The Q is the speed rating of 100 miles an hour and then mud and snow. It’s basically
an all season tire. On the side of the tire, you’ll find a max
inflation pressure. This is not what you set your tire pressures to. This is the maximum
amount of pressure that the tire can handle without exploding or at least becoming dangerous.
In our case, it has a max inflation pressure of 44 PSI. That’s actually what a lot of tires
are. Once again, that is not what you set your tires to. That is the maximum that they
can handle as far as pressure goes. You always want to follow the instructions on your door.
In the doorjamb, it usually says the recommended tire pressure for your car. Every car is different.
It’s usually between 28 PSI and 36 PSI, sometimes higher, sometimes lower. Heavy trucks have
very different tire pressures, so you always want to be careful with those, the same with
trailers. Those have very different tire pressures as well. Once again, the max tire pressure
is not something that you want to put in your tire. It’s just the maximum that the tire
can handle. Right here you’ll see the max inflation pressure
of 44 PSI. Once again, that’s not what you want to inflate your tires to. That is just
the maximum pressure that tire can handle before it gets dangerous. The last thing worth mentioning, as far as
tires go, is the sidewall of the tire. The sidewall right here is this 45 number as you
can see. It’s also the most important part of a run-flat tire. If you have one of the
newer cars that has run-flat tires, this section of the tire is actually thicker. It allows
it to be driven while flat. Even though there’s no air pressure in it, you can still drive
it to the nearest gas station or a shop to get it repaired or at least put some air in
it. A normal tire, like this one, as soon as it gets flat, the sidewall actually compresses
and the sidewall will actually start breaking up as you’re driving. Eventually the tread
separates from the bead and the tire will come off the rim and then you destroy your
wheel. Obviously that’s not the best situation. One last thing worth mentioning about tires,
today, is the different sections of the tire. This inside section right here, this is the
bead of the tire. Within this is actually a metal cable. That holds the tire tight against
the rim. A really common problem with aluminum wheels is corrosion builds up on the inside
of the aluminum wheels and it actually creates a gap between this rubber seal and the wheel.
Air will leak out and eventually your tire will be flat. That’s about it for tires today. Hopefully
you learned something. If nothing else, you can go outside and see how old your tires
are. Once again, don’t forget to visit 1AAuto.com.
Thanks for watching.

100 thoughts on “Everything That You Wanted To Know About Tires

  1. Thank you very much .
    Only one confusing part here was when you explained load rating,I didn't get was how you calculated load rating as 1477 Lbs from 92 number.

  2. Thanks for this. i got a camaro 5th gen back in April and i heard they are terrible in the snow i need to check my tires but i have no idea what i was gonna look for. thanks again.

  3. So this might be a dumb question but, if I have 32×11.5 LT15 on my jeep right now, could I get 33×12.50 LT15 without having to buy new wheels?

  4. Thank you very much for this informative video. One question: how old can a tire be with enough life and still be safe? Thank you.

  5. very helpful and very informative.i want to buy new tyres and now I have all the information I need.thanks.

  6. Awesome video! I have watched maybe 3 or 4 other Tire 101 videos and this is the BEST! I've learned sooo much more info. Thank you! =)

  7. M+S is an old rating that you should never pay attention to because summer tires that are dangerous in snow can achieve an M+S rating. It does NOT make it a good all season tire.
    Also many "Run Flat" tyres cannot be repaired. And a normal tubless tire will almost never pop off the bead when it goes flat. you can run a tire flat and destroy it down to 2 little rubber strips still seated on the bead. They rarely ever fall off.

  8. Q is a 99 mph tire. H is 130 mph tire. the higher the letter is NOT always mean the faster the tire. at 4:15 you are wrong about this. an H rated tire is 130 a Q rated is 99

  9. You forgot directional. How do you tell? I have little arrows, but do all directional tires have them? I would think so, but not sure.

  10. I have no money to purchase a set of tires right now….I have a brand new set of 4 16 inch tires in my garage. Can I use the 16 inch tires on my car temporarily that require 14 inches, until I am able to afford a new set of 14 inch tires that I will have the money for in a few weeks…@ 1 month ! If I do this exchange, could I get away with it for one month or is it risky?

  11. I bought bfgoodrich 215/r16 and put in my car suzuki grand vitara. But now the speed of the car became slow. Is that the cause! Some one told me so!

  12. Well not everything I want to know about tires. I want to know about tire thread patterns and features, what do the grooves do, what different sections of the tire do etc.

  13. Question…If a friend gives you two snow tires with a 65 profile, can you run them along with the other two summer tires with a profile of 60. We'e getting dumped in Vancouver

  14. pretty sure thats a winter tire and not all-season. M+S is usually for winter tire. and also you can see the little snowflake sign on the sidewall

  15. My car recommented tire is 215/65R 16 but it currently has on 225/50R 17, would the recommended tire pressure of 32psi work for the tire that is currently on?

  16. I am looking to replace two tires from an old farm trailer. I am not seeing as much information as the video talks about. The only information I see on it is: Goodyear 6.50-16. there is a metal piece with stamped numbers on it, but I can't read them.

  17. Stumbled upon this and was interesting what I found out about the numbers and all the information of something I had very little knowledge about except the width,radial, and percentage of the tires. Good video 1A Auto Parts.

  18. video did not tell me everything I wanted to know. did not elaborate on speed ratings nor types of tires for different seasons or hardness of tires vs expected mileage. When do I need to change the air valve?

  19. What is recommended age when no matter how good tread is that you must replace tire? Red dot? Yellow dot? Directional tires? The higher the letter is not always the faster speed rating. H. And T.

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