What Tyre Size Fits a 79 Series LandCruiser? Stock, +1, +2 and +3 Inch Guide (2026)
Tyre size is one of the first questions every new 79 Series owner asks. The factory tyre is conservatively spec'd for working durability rather than off-road capability, and even a moderate upgrade transforms how the truck behaves on gravel, sand and trails. The challenge is that going too big creates a cascade of secondary issues, including speedometer error, fender flare requirements, suspension lift needs, drivetrain stress, and ADR compliance complications. This guide covers what fits at each size step and what each step actually costs. For the full range of fitment-checked parts that pair with each tyre size step, browse our 79 Series Accessories catalogue.
All sizes below are referenced against the standard 79 Series Single Cab and Dual Cab on factory steel or alloy wheels. Speedometer error figures are approximate and depend on the specific tyre brand and tread depth. Always verify on a known-distance road test after fitment.
1. Stock Tyre Size: 265/70R16 (31.6 Inch)
The factory tyre on the 79 Series since the V8 era has been 265/70R16. Overall diameter is 31.6 inches, section width is 265 mm, sidewall aspect ratio is 70 per cent of section width. The factory tyre is typically a Bridgestone Dueler highway terrain or a Dunlop Grandtrek, with light-truck (LT) construction and a working-truck tread pattern that prioritises long life on sealed roads.
Stock size is fully legal in every state, requires no fender flares, fits the factory steel rim or 17-inch alloys equally well, and gives the factory speedometer reading. It is also the most economical tyre to replace because the size is common across the working ute segment. For owners who do not modify the truck, stock size remains the right answer for the entire ownership life of the vehicle. Stock-replacement wheels and tyres are available in our Wheels & Tyres range.
2. +1 Inch: 265/75R16 or 285/75R16 (33 Inch)
The standard first upgrade is to a 33-inch tyre. The two main options are 265/75R16 (same width as stock, taller sidewall, 31.7 inches overall, virtually identical to stock) or 285/75R16 (wider section, 32.8 inches overall, genuinely +1 inch over stock). The 285/75R16 is the much more common upgrade because the wider footprint gives noticeably better traction in sand and mud.
At 285 mm section width, the tyre is wider than the factory guard line and ADR compliance starts to require fender flares in most states. Speedometer error is approximately +4 per cent at 100 km/h (speedo reads 100, actual 96). No suspension lift required for normal driving but the tyre will rub on the inner guard at full articulation off-road. A 2-inch lift from our 79 Series Suspension range solves this completely.
3. +2 Inch: 33x12.5R16 (33 Inch Wide)
The 33x12.5R16 is a full mud-terrain or aggressive all-terrain tyre at 33 inches overall and 12.5 inches wide. It is the most popular tyre size on serious touring and off-road 79 builds. Brands include BFG KO2 and KM3, Toyo Open Country MT, Cooper STT Pro, and Mickey Thompson Baja Boss. Wider footprint gives genuinely better grip in sand and mud, and the more aggressive tread cleans itself in clay and snow.
Fender flares are mandatory at this size in most states because the tyre is significantly outside the factory guard line. A 2-inch lift is functionally required to clear the guards under suspension articulation; without it the tyre will rub on the inner liner during off-road driving. Speedometer error is around +3 per cent at 100 km/h. Tyre cost per unit jumps significantly: quality 33x12.5R16 tyres are $400 to $700 each in 2026. Wheel spacers may also be needed depending on offset; see our Wheel Spacers range.
4. +3 Inch: 35x12.5R17 or 35x12.5R16 (35 Inch)
The 35-inch tyre is the apex serious touring build and the largest tyre that fits a 79 Series without major chassis modification. 35x12.5R17 is the more popular sizing because the 17-inch wheel provides more brake clearance and a wider rim selection. The tyre is 35 inches overall and 12.5 inches wide. Speedometer error is around +10 per cent at 100 km/h (speedo reads 100, actual 90). Speedometer recalibration is typically required for legal compliance in most states.
A 2-inch lift is mandatory at 35 inch, and many owners go to a 3-inch lift for guaranteed clearance under articulation. Fender flares are mandatory and need to be the wider style (40 mm to 60 mm flare) to fully cover the tyre. Engineering certification may be required in some states for the combined lift and tyre size. The drivetrain stress at 35 inch is real: diff and CV wear is higher, fuel consumption is up 10 to 15 per cent, and acceleration is noticeably blunted. Worth it for serious off-road builds; overkill for general touring.
5. Fender Flare Requirements at Each Size
Australian ADR rules require that tyres must not protrude beyond the outer edge of the guard (or fender flare). Stock 265/70R16 is fully covered by the factory guards. The 285/75R16 is right on the edge and requires flares in some states (Victoria and NSW are strictest). Any 12.5-inch wide tyre is outside the factory guard line and requires flares everywhere. The 70 Series Store stocks fender flare kits in slim, mid and wide profiles to suit the tyre size.
Flares need to cover the tyre at full lock and full articulation, not just at static position. The flare height also needs to clear the tyre at full bump and full droop. Most owners fit 50 mm to 60 mm flares for 12.5-inch tyres which gives adequate clearance with margin. Bolt-on flares are typically 4 to 6 hours of work to fit, with bracketry that uses factory body bolt points where possible.
6. Suspension Lift Requirements at Each Size
Stock and 265/75R16 fit without any lift required for normal road use, with adequate clearance under articulation. 285/75R16 typically benefits from a 2-inch lift for full off-road clearance but is workable without. 33x12.5R16 requires a 2-inch lift for off-road articulation clearance. 35x12.5R17 requires a 2-inch lift as a minimum, with a 3-inch lift recommended for serious off-road use.
The lift kit needs to be specified together with the new tyre size because spring rate, shock travel and pinion angle all interact. Most suspension suppliers (Lovells, Tough Dog, Dobinsons, EFS, Ironman) have kits specifically labelled by tyre size compatibility. Use those kits rather than mix-and-match components. Combined lift and tyre upgrade is typically $4,000 to $9,000 fitted depending on supplier and size. Browse the matched kits in our 79 Series Suspension range.
7. Speedometer Correction and ADR Compliance
Australian ADR rules permit speedometer error of zero per cent under and 10 per cent over the actual speed (the speedo can read 10 per cent high but cannot read low). Tyres larger than stock shift the speedometer in the under-reading direction, which becomes a compliance issue at +3 per cent or more depending on starting calibration. Most factory speedometers read 3 to 5 per cent high from new, so a small tyre upgrade often just brings the speedometer toward accurate rather than under-reading.
At 33 inch the speedometer correction is borderline. At 35 inch it is mandatory in most states. Speedometer recalibration can be done via an aftermarket reflash on the ECU or a piggyback gear-pulse module. Cost is around $250 to $600. Some workshops will include this in the lift kit installation. Verify with a GPS-known-distance test after fitment.
8. Real-World Trade-offs by Size
Stock to +1 inch is the comfort zone: fuel economy stays good, speedo error is minor, no suspension lift needed for everyday use, no flares required (or only slim flares). Best for owners who do moderate touring and some unsealed road work. 33 inch is the touring sweet spot: real off-road capability, manageable drivetrain stress, fuel consumption up 5 to 8 per cent, requires lift and flares but the package is well-developed and well-supported.
35 inch is the dedicated off-road build size. Genuine capability, dramatically improved ground clearance and articulation, but every aspect of the vehicle is harder. Fuel up 10 to 15 per cent, acceleration noticeably blunted, diff and CV wear accelerated, parking and reversing more awkward. Only worth it if the truck is genuinely used hard off-road. Most touring owners are over-tyred at 35 inch and would be happier on 33.
Once your wheel and tyre package is sorted, see our guide on recommended 79 Series wheel nut torque to make sure the new rims stay safely fastened. For broader build planning, our article on 79 Series mods ranked by bang-for-buck puts a tyre and lift package in context against the other upgrades that make a noticeable difference.
Frequently Asked Questions
What is the stock tyre size on a 79 Series LandCruiser?
The factory tyre on the 79 Series is 265/70R16, with an overall diameter of 31.6 inches. The factory rim is 16-inch steel or 17-inch alloy on higher trims. The factory tyre is typically a Bridgestone Dueler or Dunlop Grandtrek in highway terrain compound.
Can I fit 33 inch tyres on a 79 Series without a lift?
You can fit 33-inch tyres (285/75R16 or 33x12.5R16) without a suspension lift for normal road driving, but the tyres will rub on the inner guard at full articulation off-road. A 2-inch lift solves this and is the standard pairing for 33-inch tyres on a 79.
Do I need fender flares with bigger tyres on a 79 Series?
Tyres wider than the factory 265 mm section typically require fender flares for ADR compliance in most Australian states. 285/75R16 is borderline; any 12.5-inch wide tyre is outside the factory guard line and requires flares everywhere. The 70 Series Store stocks vehicle-specific flare kits in slim, mid and wide profiles.
What is the biggest tyre that fits a 79 Series?
The largest tyre that fits a 79 Series without major chassis modification is 35x12.5R17 or 35x12.5R16, paired with a 2-inch to 3-inch suspension lift, wide fender flares, and speedometer recalibration. Beyond 35 inch requires chassis cuts, axle conversions and engineering certification, which is serious build territory.
Will bigger tyres reduce fuel economy on a 79 Series?
Yes. 285/75R16 typically adds 3 to 5 per cent to fuel consumption. 33x12.5R16 adds 5 to 8 per cent. 35x12.5R17 adds 10 to 15 per cent. The combination of higher rolling resistance, more rotational mass, and (often) more aggressive tread compound all contribute.
Do I need to recalibrate the speedometer for bigger tyres?
At 285/75R16 the speedometer error is typically minor and within ADR tolerance. At 33-inch the correction is borderline and recommended. At 35-inch speedometer recalibration is mandatory in most states for ADR compliance. Cost is $250 to $600 for an ECU reflash or piggyback module.
