The amount of letters and numbers on a tire sidewall can bring anyone to ask, “What does the T or H mean on tires?” Depending on whether you are a nouveau or savvy car owner, these markings could look like an algebraic equation waiting to be solved or a bunch of helpful codes. This article aims to bridge that knowledge gap and make this plethora of information more useful for all.
So, what does the T or H mean on tires? The “T” or “H” on tires pertain to their speed ratings. A T-rated tire can withstand top speeds of up to 118 mph (190 km/h), while an H-rated tire can support up to 130 mph (210 km/h). It is important to note these markings and stay within those speed limits.
To help you figure out what the T and H mean on tires, this article will go over information seen on tire sidewall markings, including load indices and speed ratings. It will also provide our picks for the best H- and T-rated tires for 2021. So, stick around and learn more about H/T tires, as this guide makes it just in time for your next tire purchase.
Decoding Tire Sidewall Markings
Since we are into the topic of understanding the service description of tires, we might as well decipher the entire sidewall markings found on them. Sidewall markings provide tons of useful information about your stock or aftermarket tires, which include the following:
The first three (3) digits of the sidewall marking indicate the tire width in millimeters. It is not to be confused with tread width, which is dependent on a tire’s aspect ratio and varies between brands. Typically, you would see a letter before these numbers (either a P, C, or LT) indicating the vehicle type compatible with the said tire.
The aspect ratio is the second pair of digits following the tire width. This number pair represents the sidewall height measured from the wheel to the top of the tread and displays in percentage.
Meanwhile, the rim diameter is the third number pair that may or may not come with a letter. In some cases, the letter that goes with the rim diameter signifies tire construction. Usually, an ‘R’ before the number pair means a radial ply construction, while a “B” or “D” means either a bias or diagonal ply construction. It is imperative to stick to the rim diameter when replacing stock rubber, especially for new vehicle owners.
Metric sizing on tire sidewalls is usually in this format – P205/65 R16. But the smaller tires on tractors, golf carts, and the like utilize flotation sizing – a system using imperial (inches) instead of metric units. The format for this system looks something like this – 31X10.50R15LT. The first, second, and last number pairs tell you the tire height, tread width, and rim diameter, respectively.
Alphanumeric and Numeric Sizing
Numeric and alphanumeric sizing systems are old, phased-out versions of the current metric and flotation sizing systems. Alphanumeric sizing (as its name suggests) was somewhat confusing – examples are A76-14 and L78-16. Unlike metric sizing, the letter in the alphanumeric format pertained to both weight capacity and tire size. Conversely, numeric sizing only consisted of two number pairs denoting tire and rim size and was used for cars and some farm applications until the ’70s.
Tire Service Description – Load Index
The load index is the number pair found on the service description bit of your tire sidewall markings. It can show as 99H or some other combination of numbers and letters. Since the assigned numerical value denotes a tire’s load-carrying capabilities, a higher load index means a higher capacity. The table below shows tire load indices ranging from 70 to 126 and their corresponding values in pounds and kilograms:
|Load Index||Pounds (lbs)||Kilograms (Kg)|
You should temper information provided by the load index with manufacturer-recommended towing limits, as well as tire and drivetrain capacities. Again, the owner’s manual is the best reference for determining your vehicle’s hauling capabilities.
Ply Rating and Load information
If you have been buying tires for a long time, you have seen the letters P, LT, ST, or XL attached to either the tire width or rim diameter portion of a sidewall marking. These letters indicate ply rating (a combination of load-carrying capability and tire type) and should not be confused with a tire’s load index or construction type.
Having no letter or a P with the tire size means a standard-load passenger-type tire with a 4-ply rating. The letters LT (Light Truck) or ST (Special Trailer) pertain to tires with heavier weight capacities and 6- to 14-ply ratings (load ranges from C to G). These tires are standard for pickups and SUVs, with ST tires strictly for use with trailers. One best practice is not to go lower than 8-ply-rated tires if you own a vehicle with a load capacity from 3/4 to 1 ton.
Looking at the sidewall markings with the metric sizing, load information, and ply rating at the top center, you should spot the maximum inflation somewhere on the left inner circle of the tire, beneath the brand name. It is easily distinguishable because of this specific format “Maximum load XX lbs., (XX Kg.) at XX psi.”
Most passenger cars typically show between 44 psi and 51 psi, while light trucks and trailers range from 50 psi to 80 psi. The maximum inflation largely depends on a tire’s ply rating and is not the same as the recommended tire pressure for your tire of choice. If you need information on cold tire pressure, refer to your owner’s manual.
Mud and Snow Markings
Some tire brands would have “M+S” markings to indicate that they have met minimum requirements to work decently on these types of terrains. Usually, this is the case with 4WD and 2WD tires with extra spaces between their tread blocks. However, note that no tire actually works seamlessly on either mud or snow – except for those with the three-peak mountain snowflake icon on them.
Although not yet a standard on all tires, these markings tremendously help consumers purchase the correct tires for their vehicles. Tires either have a directional or asymmetrical tread pattern, which works for different kinds of applications. Directional or chevron patterns help disperse water and reduce aquaplaning. Whereas asymmetrical patterns serve different purposes all at once – improved acceleration and cornering, enhanced water dispersion, and better grip – as in the case of performance tires.
DOT Codes and Other Stamps
DOT (Department of Transportation) codes contain information about the manufacturing plant, model designation, and manufacture date of a given tire. Since the other details are redundant and found elsewhere on the sidewall markings, vehicle owners usually refer only to the date and manufacturer portions of the DOT code. Industry experts deem identifying the tire age based on its manufacture date important since tires are ideally useable only for up to six (6) years from their manufacture date.
The first two digits of the DOT code specify the manufacturing plant and is especially useful for private brand tires. Meanwhile, its last three or four digits pertain to its date code. Tires manufactured before 2000 would have three digits, and post-2000 ones would have four digits. The first two numbers show the week, and the last two numbers indicate the year of manufacture.
Tire Service Description – Speed Ratings
Although the service description comes after the rim diameter information, I purposely reserved the topic for this section to better answer, “What does the T or H mean on tires?” Simply put, tire speed rating H vs T are just two of the 31-speed ratings currently used on tires. This table showing a complete outline of speed ratings (plus a brief background on how they are determined) should help you better understand speed ratings as a whole:
|Speed Rating||mph (km/h)||Application|
|A1||3 mph (5 km/h)|
|A2||6 mph (10 km/h)|
|A3||9 mph (14 km/h)|
|A4||12 mph (19 km/h)|
|A5||16 mph (26 km/h)|
|A6||19 mph (31 km/h)|
|A7||22 mph (35 km/h)|
|A8||25 mph (40 km/h)|
|B||31 mph (50 km/h)|
|C||37 mph (60 km/h)|
|D||40 mph (64 km/h)|
|E||43 mph (69 km/h)|
|F||50 mph (80 km/h)|
|G||56 mph (90 km/h)|
|J||62 mph (100 km/h)|
|K||68 mph (109 km/h)|
|L||75 mph (120 km/h)||Off-Road & Light Truck Tires|
|M||81 mph (130 km/h)||Temporary Spare Tires|
|N||87 mph (140 km/h)|
|P||93 mph (150 km/h)|
|Q||99 mph (160 km/h)||Studless & Studdable Winter Tires|
|R||106 mph (170 km/h)||Heavy-Duty Light Truck Tires|
|S||112 mph (180 km/h)||Family Sedans & Vans|
|T||118 mph (190 km/h)||Family Sedans & Vans|
|U||124 mph (200 km/h)||Sedans & Coupes|
|H||130 mph (210 km/h)||Sport Sedans & Coupes|
|V||149 mph (240 km/h)||Sport Sedans, Coupes & Sports Cars|
|Z / ZR||149 mph+ (240 km/h+)|
|W||168 mph (270 km/h)||Exotic Sports Cars|
|Y||186 mph (300 km/h)||Exotic Sports Cars|
|(Y)||186 mph+ (300 km/h+)||Exotic Sports Cars|
Where Did Speed Ratings Originate?
The system was first developed in Europe (specifically Germany’s Autobahn) in the ’60s and began with only three letters – S, H, and V. Eventually, the introduction of new speed classes and the development of tire technology led to utilizing most of the alphabet. Current speed ratings mostly appear in alphabetical order – except for the “H” rating, which retained its placement between “U” and “V.”
Running different tires in 6.2-mph steps at 10-minute increments until they meet required speeds helped establish the corresponding values for the speed ratings. At present, engineers still run this SUS (Step-Up Speed) Test but in compliance with ECE (Economic Commission for Europe) and SAE (Society of Automotive Engineers standards.
In addition to time-controlled testing and ideal riding conditions, industry leaders take other factors like ride quality/comfort, wear resistance, and cornering ability into account in determining a given tire’s speed rating. Simply put, a higher speed rating would mean improved traction and stopping power but compromised tread life. Conversely, a lower speed rating could translate to enhanced tire performance but lower top speed.
Trivia: Before 1991, speed ratings were mixed with tire size information that confused some consumers. The service description was added on sidewall markings beginning 1991 onward to address this, separating the speed rating and load index from the rim diameter information.
Up Close – H vs T Tires
Out of all the speed ratings, tires with “H” and “T” markings are the most frequently used on sedans, family cars, and SUVs. Under optimal riding conditions, these specific tires can tolerate speeds ranging from 118 mph (190 km/h) to 130 mph (210 km/h).
Specifically, H-rated tires fall under the grand touring category and are best for sport/luxury coupes, sedans, and amateur racing cars (despite not being designed for full-fledged performance vehicles). Meanwhile, T-rated tires fall under the standard touring and all-season categories and are ideal for family cars and minivans.
While both speed ratings offer handling benefits due to their softer rubber compounds and sturdier tire construction, H/T tires have some tradeoffs. Based on mile wear tests carried out by Consumer Reports, T-rated tires are proven to have longer tread life compared to H-rated knobbies. This benefit somehow compensates for the lower top speed these tires can accommodate.
On the other hand, H-rated tires continually become more common as factory tires on some popular automobile brands. Despite their shorter life span, H-rated tires can meet tire safety standards and are better suited for higher levels of braking, handling/cornering, and acceleration – perfectly matching the enhanced capabilities of recent family cars and sedans.
Top Picks for 2021
Since we are on the topic of H/T tires, it would make sense to give you a list of highly recommended H- and T-rated tires. While there are tons of reputable tire brands in the market, these top picks are lauded by some of the most respectable automakers and automotive publications:
|T-rated Tires||H-rated Tires|
|Michelin Defender LTX (view on Amazon)||Michelin CrossClimate 2|
|Goodyear Ultra Grip Winter or a higher-speed-rated tire such as Goodyear Assurance WeatherReady||Bridgestone Blizzak WS90 or a higher-speed-rated tire such as Bridgestone Turanza Quiettrack|
|Cooper Evolution H/T||Yokohama Avid Ascend GT|
|Bridgestone Dueler A/T Revo 3||Michelin Defender T+H (view on Amazon)|
|Pirelli Scorpion All Terrain Plus||Cooper CS5 Ultra Touring – H/V|
|BFGoodrich Advantage T/A Sport LT||BFGoodrich Advantage T/A Sport LT|
|Continental CrossContact LX25||Continental CrossContact LX25|
|Yokohama AVID Touring-S||Yokohama Geolandar A/T G015|
|Yokohama iceGUARD iG52c (winter tire)||General AltiMAX RT43|
|General AltiMAX Arctic 12||Hankook Kinergy 4S2 or a higher-speed-rated tire such as Hankook Ventus ST RH06|
|T-rated Tires||H-rated Tires|
|Cooper Discoverer AT3 4S (for SUVs)||Michelin X-Ice Xi3 (winter tire)|
|General Grabber A/TX (SUV, 4×4)||Firestone WeatherGrip|
|Toyo Open Country A/T III (view on Amazon)||Dunlop Direzza DZ102 (view on Amazon)|
Can You Mix H and T-Rated Tires?
Vehicle owners are discouraged from doing this, as using tires with different speed ratings can result in premature tire degradation. Furthermore, it goes against one of the best practices for improving grip on slippery surfaces: putting tires that have the most tread at the rear.
Another danger with mixed speed ratings is the tendency to oversteer, which adversely affects vehicle handling. Luckily, placing the T-rated tires on the front axle (regardless of the axle driven) prevents this from occurring. Note, however, that mixing tire speed ratings should be done as a last resort and reserved only for worst-case scenarios.
Can I Use H-Rated Tires Instead of V?
Opting for H-rated tires is fine – provided that you keep to the 130-mph top speed limit instead of the 149-mph limit supported by a V-rated tire. To add, make sure to use the same speed rating on all fours for best performance.
As a precaution, never opt for tires with a speed rating two tiers lower than the original requirement for your vehicle. Not only does it increase the chances of tire failure at high speeds, but it can also invalidate your insurance.
What Does T/H Mean on Michelin Tires?
The H or T markings on Michelin tires indicate the same speed rating as on any other tire brand. But unlike most tires which are only given a single rating, Michelin tires can accommodate a top-speed range between 118 to 130 mph (190 to 209 km/h).
What Does 94T Mean on a Tire?
“94T” markings on a tire denote its service description. These numbers indicate the specific tire has a load-carrying capacity of 670 Kg (1,477 lbs.) when adequately pressurized and a speed rating of 118 mph (190 km/h).
Can I Use T Tires on Race Cars?
Using T-rated tires would be inadequate, as 118 mph is considered slow and too delicate for race cars and other high-performance, sports-oriented wheelers. Z-rated tires (or above) will serve the purpose better in such settings. For amateur racecars, the least you can go for is an H-rated tire.
Conclusion – What Does H/T Mean on Tires?
In summary, H and T markings on tires refer to the maximum speeds they can support – given payload capacity, recommended tire pressure, and ideal road conditions are met. H-rated tires can withstand up to 130 mph (210 km/h), with T-rated ones supporting up to 118 mph (190 km/h). If you are driving anything from a standard sedan to a sport SUV, you are most likely in need of one of these.
Now that you know what H/T on tires signify, it is equally important to understand that these speed ratings are only true for brand-new tires that have not experienced damage, puncture, or any form of repair. That said, it is always advisable to go for new over secondhand tires when buying replacements for your car. Doing so ensures you adhere to the speed limits appropriate to your vehicle.