Tyre guide

Buying Guide

A practical introduction to tyre sizing, sidewall markings, load and speed ratings, and the questions to ask before choosing a replacement tyre.

HRB Pacific first-party archiveOriginally published 27 Apr 2022 · Updated 4 Oct 2026

Choosing replacement tyres affects safety, handling, ride comfort and operating cost. Start with the vehicle tyre placard and owner’s manual—not appearance or price alone. The placard is commonly found on a door opening, inside the glove box or near the fuel filler and records the manufacturer’s approved tyre size, load information and cold inflation pressure.

This guide is intended for passenger vehicles and light commercial vehicles. Heavy vehicles have additional requirements under the National Heavy Vehicle Regulator and should be assessed by a suitably qualified heavy-vehicle tyre professional.

NSW scope: regulatory and roadworthiness guidance on this page is based on NSW requirements. National Australian Design Rules are used only for technical tyre markings and rating tables. If the vehicle is registered or used outside NSW, check the relevant local authority before changing tyre specifications.

How to read a tyre sidewall

A marking such as 205/55 R16 91V can be read as follows:

205 is the nominal section width in millimetres.
55 is the aspect ratio: the sidewall height is 55% of the nominal width.
R identifies radial construction.
16 is the wheel rim diameter in inches.
91 is the load index. It is a code, not a kilogram figure.
V is the speed symbol under specified test conditions; it is not permission to exceed any legal speed limit.

P commonly identifies a passenger tyre and LT a light-truck tyre. Other service markings may vary by product. A qualified fitter should interpret the complete marking for the intended vehicle and load.

Load index and speed symbol

For a vehicle used in NSW, replacement tyres must provide the load capacity required by the vehicle placard and manufacturer. Speed requirements depend on the vehicle and applicable NSW standards, so do not assume a lower rating is acceptable. Confirm both values before purchase.

Common load index values (60–126)

Common load indices and maximum load per tyre
Load index	Load per tyre (kg)	Load index	Load per tyre (kg)
60	250	94	670
61	257	95	690
62	265	96	710
63	272	97	730
64	280	98	750
65	290	99	775
66	300	100	800
67	307	101	825
68	315	102	850
69	325	103	875
70	335	104	900
71	345	105	925
72	355	106	950
73	365	107	975
74	375	108	1,000
75	387	109	1,030
76	400	110	1,060
77	412	111	1,090
78	425	112	1,120
79	437	113	1,150
80	450	114	1,180
81	462	115	1,215
82	475	116	1,250
83	487	117	1,285
84	500	118	1,320
85	515	119	1,360
86	530	120	1,400
87	545	121	1,450
88	560	122	1,500
89	580	123	1,550
90	600	124	1,600
91	615	125	1,650
92	630	126	1,700
93	650	—	—

Common speed symbols

Tyre capability under specified test conditions—not a road speed limit
Speed symbol	Speed (km/h)
F	80
G	90
J	100
K	110
L	120
M	130
N	140
P	150
Q	160
R	170
S	180
T	190
U	200
H	210
V	240
W	270
Y	300

These tables show common passenger and light-commercial values and are only for interpreting sidewall markings. A load index is the maximum load per tyre under specified service conditions; it is not the permitted vehicle or axle payload. Replacement tyres must meet the applicable placard and manufacturer requirements. Where a light-commercial tyre shows two load indices, the first normally applies to single fitment and the second to dual or twinned fitment. A speed symbol describes tyre capability under specified test conditions—it is not a legal or recommended driving speed or permission to fit a lower original-equipment rating. Allowable load may also reduce at very high speeds; follow the tyre manufacturer’s data.

Sources: ADR 23/03 — Passenger Car Tyres; ADR 96/00 — Commercial Vehicle Tyres; NSW Vehicle Standards Information 09.

Temperature and treadwear grades

Some tyres display US Uniform Tire Quality Grading (UTQG) temperature and treadwear grades. These comparative test results are not an Australian fitment approval and should not be treated as a prediction of real-world life. Driving style, alignment, pressure, load, road surface and maintenance all affect wear.

Match the tyre to the vehicle

Use the placard and owner’s manual to confirm size, construction, load capacity, speed capability and cold pressure. Tyres fitted to the same axle should have compatible size and construction. All-wheel-drive and four-wheel-drive systems can also have strict circumference and tread-depth matching requirements; follow the vehicle manufacturer’s instructions.

A temporary spare or space-saver is for emergency use only. Follow its marked pressure, speed and distance limits and the vehicle handbook.

Considering a different size?

Do not assume that a visually similar or popular alternative is suitable. In NSW, a qualified tyre professional should check wheel approval, overall diameter, clearance through the full steering and suspension travel, load capacity, inflation requirements, speedometer effects and whether the change requires VSCCS certification.

Match the tyre to the work

How is the vehicle used?

Consider normal roads, distance, load, weather and whether the vehicle is used for urban driving, highways, work sites or off-road travel. The appropriate pattern and construction depend on the most demanding conditions the vehicle regularly encounters.

For regular towing or heavy loads, use the vehicle and trailer documentation to check gross and axle limits, tyre load capacity and the manufacturer’s pressure guidance. Never rely on the tyre sidewall maximum as the normal everyday pressure.

Which category is appropriate?

Touring, performance, highway-terrain, all-terrain and mud-terrain tyres are designed around different priorities. A professional installer can help balance comfort, noise, grip, durability and off-road capability.

Does price guarantee value?

Purchase price is only one part of value. Suitability, safety, expected wear, service support and correct installation should be considered together.

Before installation

Confirm the exact size, load index and speed symbol against the placard and handbook.
Tell the fitter about towing, frequent heavy loads, off-road use and any wheel, suspension or drivetrain modification.
Confirm whether the vehicle has directional, asymmetric, staggered, run-flat or tyre-pressure-monitoring requirements.
Ask the store to confirm current specifications, availability, installation, balancing and disposal charges.

General guidance only: for NSW vehicles, always follow the vehicle manufacturer’s handbook and tyre placard, the tyre manufacturer’s instructions and current NSW roadworthiness and modification requirements. If in doubt, ask a qualified NSW tyre fitter or Transport for NSW.

Useful official references include NSW Vehicle Standards Information, NSW VSI 09 and the Australian Government’s VSB 14 technical guidance.