Biggest tyres for a D-Max RG: will 33s fit?

For an RG D-Max, assess the intermediate 265/70R17 before a 285/70R17 33-inch package. Relative to the cited 255/65R17 reference, those add 39.5 mm and 67.5 mm in nominal diameter. The 33-inch option is not simply the same upgrade with a little more tread.

Australian RG D-Max, using Isuzu's 25.5MY tyre examples. The ROH table is its standard RG application. X-Terrain, Blade, earlier TF vehicles and certified conversions need separate checks.

What is the biggest tyre to consider?

The 25.5MY brochure lists different tyre packages by grade. Keep factory 17-inch SX/X-RIDER and 18-inch LS-U examples in their stated scope. A two-inch lift does not establish tyre clearance at full compression or change the state diameter allowance.

The table is a decision shortlist. It does not claim a tested maximum tyre size for every stock vehicle in this generation. The source-backed sizes, dimensions and conditions below let you narrow the package before an installer checks it.

What tyre sizes came on this vehicle?

These are scoped examples, not a size chart for every year or variant. Match the tyre placard and wheel markings on your own vehicle. Read the original reference.

Read the tyre sidewall

How much bigger are these tyres?

The largest example here adds 67.5 mm in nominal diameter, or 33.8 mm in nominal radius, relative to 255/65R17. These are arithmetic dimensions from the sidewall code, not measured sizes of a particular product. Tread, construction and the manufacturer's specification can change the real unloaded diameter. The radius change is not a promise of ground clearance on a loaded vehicle.

What real tyre specifications change

The following are exact product rows from the tyre makers, checked on 13 November 2026. They illustrate dimensions and rim approvals, not a recommendation that each product suits every vehicle in this guide. Load and speed suitability still need confirmation.

Read the exact version in the quote. An LT, passenger or XL version may have a different construction and specification despite sharing the same nominal size. A supplier must match the chosen tyre to the rim, load and vehicle, rather than using the inch label alone.

The metric calculation is wheel diameter in inches × 25.4, plus twice the section width × aspect ratio. Flotation dimensions such as 35x12.50R17 are nominal too.

Will the biggest option fit stock or with a two-inch lift?

A wheel that turns freely on a level workshop floor has not completed a clearance check. Ask the installer to assess the exact tyre and wheel at both steering locks and throughout suspension movement, including loaded compression. Include body liners, mudflaps, suspension components and the spare location.

A suspension lift changes the resting position. It does not, by itself, prove that a larger tyre clears the body at full compression. Lowering the wheel offset can gain room on one side while moving the tyre closer to another obstruction.

Blade and X-Terrain need their own specification rather than being treated as ordinary RG trim names. For an SX work ute, start from its actual placard and wheel width; a catalogue photo of a higher-grade D-Max is not your baseline.

Which size would we choose for daily driving or touring?

Mostly road and everyday use: start with a suitable tyre in the manufacturer-designated size. A different tread can change the look without increasing diameter.

Touring and mixed tracks: compare the original diameter with 265/70R17. In nominal terms that changes diameter by +39.5 mm and section width by +10 mm. Decide whether that change is useful before arranging a fitment check.

A larger off-road build: price the complete 285/70R17 package, including the wheel, clearance work and speedometer check. Establish whether a lawful approval path exists before buying the package. Comparison dimensions are not an approved upgrade list.

Are 33s or bigger tyres legal in Queensland and Victoria?

The inch label cannot answer that. The 285/70R17 comparison is 67.5 mm taller in nominal diameter than this guide's 255/65R17 reference. That reference is a comparison input, not a finding that it is your vehicle's largest eligible manufacturer option.

Queensland: for eligible MC, NA and NB1 vehicles, the current guidance allows up to 50 mm more tyre diameter, subject to the other requirements. For an eligible off-road 4WD, up to 75 mm combined lift can avoid certification when it comprises no more than 50 mm suspension lift and 25 mm tyre-radius increase, with no body blocks. A certified LS9/LS10 lift still has a 50 mm tyre-diameter cap. Queensland's prescribed design-new or UN diameter method must be used; this article's nominal calculator is not a legal pass/fail result. See the Queensland rules and worked example.

Victoria, including Melbourne: VSI 8 provides a conditional 75 mm combined-lift alternative for eligible off-road 4WDs, with up to 50 mm suspension lift and 50 mm more tyre diameter. A suspension kit must be designed and tested for the make, model and variant at the combined height, with a written suitability statement retained. Coverage, full-travel clearance and ESC requirements also apply. See Victoria's full conditions and VASS pathway.

A two-inch lift is 50.8 mm, so a product's marketing name is not evidence that it stays within a 50 mm limit. Confirm the actual lift and complete package. Vehicles outside these categories, above 4.5 tonnes GVM or registered elsewhere need the applicable rules.

What to confirm before buying

• Your exact grade, build date and original designated tyre size.
• The chosen tyre model's published diameter, load and speed specification and approved rim width.
• Loaded clearance through steering and suspension movement, including the matching spare.
• The applicable state tyre-diameter, track and combined-lift requirements, with any approval documents obtained before the work.

Questions owners ask before fitting bigger tyres

Will a two-inch lift stop all tyre rubbing?

No. It changes the resting position, while the tyre must still clear at the suspension's compression limit and both steering locks. Check the exact tyre dimensions, wheel width and offset. Do not alter steering stops merely to create tyre clearance.

Does a two-inch D-Max lift automatically allow 33s?

No. Suspension height and tyre diameter are separate limits. The 67.5 mm nominal increase from this reference is a reason to establish the correct manufacturer baseline and legal diameter method before ordering, even if a workshop can make the tyre physically clear.

Does an all-terrain tyre in the same size need a fitment check?

Yes. The manufacturer tables above show why nominal size is not an exact physical measurement. Check the particular construction, published diameter, approved rim range and load/speed requirements before replacing the original tyre.

See the size and stance on your own Isuzu D-Max RG

Once you have a technically suitable shortlist, compare the look against your own paint, tray, canopy or touring equipment. See wheels and tyres on your vehicle in Nordak. A generated build is a visual concept and cannot confirm mechanical clearance.

Read the companion wheel size and offset guide before choosing an aftermarket wheel.