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Difference in tires sizes? help?

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what is a difference between 195/65R15 and 195/60R15? I didnt know if I could get the 60's or not when my tire says 65. Is it possible? I have a 2005 hyundai elantra

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  1. The tire size branded on the sidewall provides a significant amount of information about the tire's intended purpose, dimensions, load capacity and high temperature/high speed durability.

    Our primary example will be based on variations of the 225/50R16 size, although other sizes will appear where appropriate.

    Service Type

    Most tire sizes begin with a letter or letters that identify the type of vehicle and/or type of service for which they were designed. The common indicators are as follows:

    P225/50R16 91S

    P = When a tire size begins with a "P," it signifies the tire is a "P-metric" size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of P-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.

    225/50R16 92S

    If there isn't a letter preceding the three-digit numeric portion of a tire size, it signifies the tire is a "Metric" size (also called "Euro-metric" because these sizes originated in Europe). While Metric tire sizes are primarily used on European cars, they are also used on vans and sport utility vehicles. Euro-metric sizes are dimensionally equivalent to P-metric sizes, but typically differ subtly in load carrying capabilities.

    T125/90D16 98M

    T = If a tire size begins with a "T," it signifies the tire is a "Temporary Spare" ("space saver" or "mini spare") that was designed to be used temporarily only until a flat tire can be repaired or replaced.

    LT245/75R16 108/104S

    LT = If a tire size begins with "LT," it signifies the tire is a "Light Truck-metric" size that was designed to be used on vehicles that are capable of carrying heavy cargo or towing large trailers. This includes medium and heavy-duty (typically 3/4- and 1-ton load capacity) pickup trucks, sport utility vehicles and full-size vans. Tires branded with the "LT" designation are the "little brothers" of 18-wheel tractor-trailer tires and are designed to provide substantial reserve capacity to accept the additional stresses of carrying heavy cargo.

    7.50R16LT 112/107Q, 8.75R16.5LT 104/100Q or 31x10.50R15LT 109Q

    LT = If a tire ends with "LT," it signifies the tire is either an earlier "Numeric", "Wide Base" or "Flotation" Light Truck size designed to be used on vehicles that are capable of carrying heavy cargo and towing trailers (Numeric sizes), use 16.5-inch diameter rims (Wide Base sizes) or are wider, oversized tires designed to help the vehicle drive on top of loose dirt or sandy surfaces (Flotation sizes). This includes light, medium and heavy-duty (typically 1/2-, 3/4 and 1-ton load capacity) pickup trucks and sport utility vehicles. Tires branded with the "LT" at the end of their size designation are also the "little brothers" of 18-wheel tractor-trailer tires and are designed to provide substantial reserve capacity to accept the additional stresses of carrying heavy cargo.

    195/70R15C 104/102R

    C = If a Euro-metric sized tire ends with a "C," it signifies the tire is a "Commercial" tire intended to be used on vans or delivery trucks that are capable of carrying heavy loads. In addition to being branded with the "C" in their size, these tires are also branded with their appropriate Service Description and "Load Range" (Load Range B, Load Range C or Load Range D).

    ST225/75R15

    ST = If a tire size begins with "ST," it signifies the tire is a "Special Trailer Service" size that was designed to only be used on boat, car or utility trailers. ST-sized tires should never be used on cars, vans or light trucks.

    Section Width

    Following the letter(s) that identify the type of vehicle and/or type of service for which the tire was designed, the three-digit numeric portion identifies the tire's "Section Width" (cross section) in millimeters.

    P225/50R16 91S

    The 225 indicates this tire is 225 millimeters across from the widest point of its outer sidewall to the widest point of its inner sidewall when mounted and measured on a specified width wheel. This measurement is also referred to as the tire's section width. Because many people think of measurements in inches, the 225mm can be converted to inches by dividing the section width in millimeters by 25.4 (the number of millimeters per inch).

    225mm / 25.4 = 8.86"

    Sidewall Aspect Ratio

    Typically following the three digits identifying the tire's Section Width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.

    P225/50R16 91S

    The 50 indicates that this tire size's sidewall height (from rim to tread) is 50% of its section width. The measurement is the tire's section height, and also referred to as the tire's series, profile or aspect ratio. The higher the number, the taller the sidewall; the lower the number, the lower the sidewall. We know that this tire size's section width is 225mm and that its section height is 50% of 225mm. By converting the 225mm to inches (225 / 25.4 = 8.86") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of 4.43". If this tire were a P225/70R16 size, our calculation would confirm that the size would result in a section height of 6.20", approximately a 1.8-inch taller sidewall.

    Internal Construction

    A letter (R in this case) that identifies the tire's internal construction follows the two digits used to identify the aspect ratio.

    P225/50R16, P225/50ZR16

    The R in the P225/50R16 91S size identifies that the tire has a Radial construction in which the tire's body plies "radiate" out from the imaginary center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.

    If the R in the size was replaced with a D (225/50D16), it would identify that the internal tire body plies crisscross on a Diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.

    If the R in the size was replaced with a B (225/50B16), it would identify that the tire body plies not only crisscross the tire on a diagonal as before, but that they are reinforced with belts under the tread area. This type of tire construction is called "Belted." Tires using this construction are practically extinct.

    Speed Rating

    Today, the only tires that continue to include the speed rating "in" the tire size (P225/50ZR16) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description (which will be covered shortly).

    Tire and Wheel Diameter

    P225/50R16 91S

    The 16 indicates the tire and wheel diameter designed to be matched together.

    Tires that have a rim diameter expressed in inches (P225/50R16, as well as 8, 10, 12, 13, 14, 15, 17, 18, 19, 20, 22, 23, 24, 26 and 28) are called "inch rim" sizes, are the most common type of tire size and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.

    While not as common, two additional "unique" types of tire/wheel diameters are still in use today.

    Tires and wheels that have a rim diameter expressed in "half" inches (8.00R16.5LT, as well as, 14.5, 15.5, 17.5 and 19.5) are used on some heavy-duty trailers, heavy-duty light trucks and box vans.

    Tires and wheels that have a rim diameter expressed in millimeters (190/65R390, as well as, 365 and 415) are called millimetric sizes. Michelin initiated millimetric sizes for their TRX tires that saw limited use on many different car models in the late 1970s and 1980s.

    Michelin PAX System run flat tires have been introduced as an integrated wheel/tire system on a very limited basis as Original Equipment (O.E.) in North America. An example PAX System size of 235/710R460A 104T expresses tire and wheel dimensions in millimeters (235 mm Section Width, tire Overall Diameter of 710 mm and a 460A mm rim diameter, with the "A" in 460A signifying these tires feature "asymmetric" beads in which the outside bead (450 mm) and inside bead (470 mm) are actually different diameters.

    All of these "unique" tire/wheel diameters were developed specifically because the tire and wheel design or intended vehicle use required them to be different than conventional tires and wheels. All of these tires and wheels feature bead profiles that have a different shape than traditional "inch rim" sizes.

    Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.

    It is critical that the tire and wheel diameters are always confirmed to match before the tire is mounted on the wheel.

    Service Description

    P225/50R16 91S

    The 91S represents the tire's Service Description. A Service Description identifies the tire's Load Index and Speed Rating. Service Descriptions are required on all speed rated (except for Z-speed rated) tires manufactured since 1991. For more information on Service Descriptions, click here.


  2. Mommie, Here's exactly what I recommend doing. Go to: tirerack.com and look at any of their 18 brands of tires. When you open a particular one up, hit your mouse button under the word Spec. A page will open that will give you all the physical measurements for every size tire. The big thing to be concerned with is when changing tire sizes is the circumference. Changes in tire sectional dimensions (60 instead of 65) has a smaller circumference than the one that's supposed to be on the car will whack-out your speedometer calibration. In your case dropping to a 60 tire instead of a 65 will speed-up the speedometer.

    When choosing anything other than the standard tire look at the far left column for a given size. At the heading for that column are the letters RPM. In tire language that means *revolutions per mile. When sizing up or down always shoot for no more than 20 revolutions difference from your standard sized tires. This step will keep your speedometer within 2-3 mph of where it should ordinarily be.

    After checking tirerack's site the 195/6015 (being a smaller circumference tire) will roll 23 more times per mile. It will speed-up your speedometer at all speeds.  Just be very aware of it.

  3. I think you got your applications backwards.

    Your Hyundai has 195/60R15 88H sized tires.  The PT Cruiser would have P195/65R15 89T sized tires.

    The differences are that the PT Cruiser's tires are taller - to the tune of about 3/4" which will make your odometer and speedometer read lower than you are actually going.  This shouldn't be enough to cause body interference but it could.

    The PT Cruisers tires also have a lower Speed Rating which combined with the taller sidewall means they will not handle as well as the tires your car was engineered to have.

    You can ignore all of the other answers above.  None of those people even seem to understand what you are asking.  

  4. The 195/60R15 has a slightly smaller diameter.  You can get the exact numbers from this website:

    http://www.miata.net/garage/tirecalc.htm...

    A smaller diameter tire will effect the accuracy of your speedometer, but that site will tell you how far off you'll be.

  5. 195 means 195 cm from center of tire to rim and the 60 or 65 means 60% or 65% of tread pattern-either will fit the only diffence is that the tire will be slightly wider and you probably wont notice the difference

  6. The first number is the width of the tire. Your tire is 195 mm wide.  The second number is what percent of the width that the side wall is tall. Your tires are about 126 mm tall from the top of the tire to where it mounts on the rim. Basically it can be referred to as the tires profile. The R tells you that the tire's treads run radially around the tire. The 15 means that your tires are made to be mounted on 15'' rims. If you put the new tires on, your speedometer will be a bit off, but your computer can be adjusted to fix this.

  7. Yes they will work on your car. The amount of difference is minimal. It may affect your speedometer by 1-2 MPH not enough for the average driver to notice.

  8. its the diameter of the tire 65 is bigger 60 is smaller

    i would prefer the 60

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