The question of ‘how much bigger tyres can I fit’ on your 4WD comes up regularly, and one of the most overlooked pieces of information is what the law is, and what the consequences are of running a vehicle that has tyres bigger than they are allowed to be.
VSB 14 states that you can increase the tyre size by 50mm. What it doesn’t make clear though, is that in some cases you can actually go more than this.
Here’s the exact wording “Must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the vehicle manufacturer for that vehicle.”
What this refers to is simple; its any model vehicle in your range. You should be able to compare tyres sizes for the base model, middle models and top of the range models and go 50mm bigger than the largest tyre in that year range.
If you are wanting to change tyre sizes, please have a read of this first – Fitting bigger tyres to your 4WD; what you need to know.

How much bigger tyre can you go?
How can you fit bigger tyres?
You are allowed to go 50mm bigger than the largest tyres found in your model range. For example, if we look at our Isuzu Dmax, it came with 245/70/16 tyres, which are 749.4mm in diameter.
For more information on Dmax tyre size options from the factory, look at your tyre placard on the A pillar. Whilst I wasn’t going for the biggest tyres on our Dmax, I wanted the next common size up.

The placard on our Dmax, showing the factory tyre size
If you want a tyre size calculator, check this out – https://www.exploroz.com/Vehicle/Tyres/SizeCalc.aspx
Most people would naturally think that the maximum tyre size is 799.4mm. However, the LSU (a fancier model) came out with 255/65/17 tyres, which are 763.3mm.
Providing the changes between the models are purely cosmetic (chrome bits, fancy dashboards etc) you can go 50mm bigger than the biggest tyres in your model range. This means the maximum size is actually 813.3mm. This is perfect for us, as a 265/75/16 (one of the most popular tyre sizes around) is 803.9mm.
This exceeds the 50mm increase for the SX versions, but is within the 50mm increase for the LSU versions, and as a result we’ve gone for them. At 54.5mm bigger in diameter than the stock tyres they are a fair increase, but they actually correct the speedo and give us about 25mm more clearance everywhere under the vehicle.
Now, I want to clarify the cosmetic comment; if there are changes to the driveline, suspension, brakes or anything else between models then this will not apply, as the engineering is different.
Having chrome door handles and a nicer stereo though, is not going to change the way your vehicle handles on the road (and this is what it refers to). You can’t compare a Ford Ranger Raptor to a Ford Ranger for example, as they are not the same vehicle by a long shot.

Make sure you are comparing models with only cosmetic differences
For a random fact, the Dmax wheel offset is positive 33mm. If you want more information like this, including the Dmax tyre size for different models head over to Redbook and look through the different models – SX, LSM, LSU etc.
Now, bigger tyres on your 4WD are good in many ways, but like everything, have a number of downsides to 4WD modifications. Don’t forget about them when it comes to fitting them to your 4WD.

Our Dmax with 265/75/16’s
What if you want to go bigger?
If you want to go to larger tyres (like 33 inch tyres on a Dmax) then it will be illegal straight off the bat, unless you get engineering paperwork to back it up. This can be as simple as getting an engineer to sign it off, but more than likely you’ll have to do lane change tests and lots of mucking around.

If you want to go even bigger, you’ll need engineering
Check with your local authorities
Please, before you fit bigger tyres, give your local road authority a call, and ask them the question. Stick within the regulations and you’ll be much better off!
Is your 4WD legal? If not, you can be in hot water really, really quickly.
If you aren’t sure of what’s legal, have a read of this; 32 ways to make your 4WD illegal.

Bigger 4WD’s come with bigger tyres straight off the bat
so will a 265 x 75 x 16 tyre fit under the front guards of a dmax with out rubbing or what would you recomend
Hi Susan,
Yes, providing the suspension isn’t sagged
Aaron
Hi there,
I am wondering if you have found any noticeable drawbacks in handling/steering or changes to the way the dmax drives since fitting the new size? Some people comment on power loss.
I have one with stock 245/70r16’s that need replacement. I am looking at 245/75r16 as the demo I drove with 265 felt heavy in the steering. Any thoughts ?
Cheers
Hey mate,
I swap between the tyres a fair bit. I can’t feel any obvious differences, but it does brake worse, get marginally worse economy and you do lose some power and torque. With all the weight, wind resistance and the trailer it is noticeably slower than when I got the vehicle.
Life is a compromise; I wanted the extra clearance and will put up with the negatives
Aaron
Hi,
Cool article, but there is something I’m questioning. When you say you can actually fit larger so long as it is within the same model range, what if those tyre sizes from the upgraded models aren’t actually on your tyre placard? I have an amarok trendline that came with 245/70/16 and that is the only size on my door placard. But looking at the amarok ultimate version, it came with 255/55/19. Therefore, a set of 265/70/17 (or similar) would be legal on a 2014 ultimate, but not my 2014 trendline. As far as I can see the changes are only cosmetic and I’d probably need flares.
So is using any model in the range your interpretation of the rules, or am I missing something completely here? The way I interpret “Must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the vehicle manufacturer for that vehicle”, is “That Vehicle” refers to mine specifically and not others in the same year/range.
Id love to be proven wrong, as I want to legally run a 265/70/17, but its about 4mm to big for legal purposes. Don’t want to be defected miles from home on a family trip! Or worse yet not have insurance pay out.
Would you use the same interpretation for wheel offset? The variance in the 2014 Amarok range is nearly 30mm from memory.
Cheers,
Micheal.
Hey Michael,
You raise an interesting question, and one I have wondered about myself. I would say it has to be in the same year range, and the only changes could be trims, upgraded stereo’s etc, without touching any of the drive line, suspension, brakes etc etc. I don’t know enough about the Amarok’s to comment, but have confirmed my thinking on this is correct with the Department of Transport and a few engineers over here in WA.
All the best
Aaron
I have a 2019 dmax extra cab six which comes std with 245/70/16 tyres and after reading your posts believe I can go to 265/75/16 tyre size. My dmax is automatic and was wondering if you could comment on the gear change when towing a caravan and also whether there is a difference when driving empty with an increase in tyre size. To clarify, when driving down to perth with my caravan, there seems at times to be a lot of changes between probably between 4 Th and 5 Th when towing between 90 and 100 km. Not sure I have expressed my question very well but would appreciate your thoughts
Hey guys, I just stumbled upon this article regarding tyre upgrade’s. I have gone down to the Queensland department of transport and shown them this article as I also own an sx 2015 d-max ute that originally came out with 245/70r16 and I’m wanting to upgrade to 265/70r17 which puts me at 54mm 4mm over the legal limit. The department of transport Officer was a really cool lad he said that it was correct and that transport would go off the larger specs of the upgraded models. But he did say that the police aren’t educated enough in vehicle modifications and this particular legalisation in the vsb 14 regulations wouldn’t be know to them and that they would only go off your placard. What iam asking is does anyone know exactly where in the VSB 14 where it references the words manufactures vehicle range. The VSB 14 is Australian wide from what I can see. Any help locating the exact referencing would be much appreciated. As I’m going to approach my insurance company and state the referenced regulations and make sure I can get cover with the upgraded tyres cheers in advance.
Hey Gavin,
I know what you are asking. The tyres are basically the last part of the gear ratio. By fitting bigger tyres you make the motor work harder, and you will use more fuel. What weight is the van? I now tow a 2 – 2.3 tonne trailer and it works pretty hard without a remap, which may be the next port of call for me.
See if you can borrow some tyres and test it out, but at the end of the day you’ll have to choose between economy power vs using more fuel and having less power
Aaron
Hey Adrian,
I’m sure you’d have some disagreements with the police. I have an email copy in my Dmax stating its legal, from the Department of Transport in WA.
However, you can read the exact wording here https://www.infrastructure.gov.au/vehicles/vehicle_regulation/bulletin/files/NCOP11_Section_LS_Tyres_Suspension_Steering_Nov_2015_v4.pdf
Read 4.2.4. You can also confirm with various independent engineers
All the best mate
Aaron
Hi Aaron,
My van size length is 21 ft 7 inches and gvm of 2750 kms. I have to say the towing capability is impressive of the dmax. My last measured trip for fuel consumption was 14 litres to the 100 kms over 352 from Bunbury up sw hwy to pinjarra across the scarp to Boddington then up to Neerabup where I filled up. I have to say I was impressed. One on the main reasons I am looking at bigger tyres is for a little more clearance and better performance on sandy beaches where I spend a lot of time fishing.
Cheers and thanks
Gavin
Hey Gavin,
That’s some great fuel economy for sure. I would see if you can borrow some tyres to test with, as I reckon you’ll use at least 10% more fuel going to a 265/75/16.
Whether that is worth it is up to you; you’ll get better clearance, but less power and torque, less range and you’ll pay more to travel.
All the best mate
Aaron
Dear Aeron,
I have the LSU with 255/65/17 stock tyres, which are 763.3mm.
Do you think if i can safely mount 255/70/18 tyre and wheel on my d-max?
This size makes 814.2mm which is approximately 1.0mm exceeding the 763.3+50=813.3mm limit you advised.
Is this acceptable,
Thanks for these valuable infos
Hi Hasan,
Safely, yep. Legally, no. I wouldn’t recommend going to an 18 inch rim either. Better to stick with 16’s or 17’s for cheaper prices, better availability and they will perform better off road
All the best
Aaron
Hi Aaron,
I’m in WA as well, I have a 2019 Nissan Navara Np300. I have stock 255/70/16 and I was thinking going either 265/75/16 or 285/70/17
Which would be better? With no running or any issues presenting itself
And which could I get a 1 inch lift with?
The Nissan Ntrek has 32.2 inch tyres
Thank you
Hi Lisa,
I don’t know much about the Navara’s. You can go 50mm larger in tyre size than the largest in the range. From there, you will have gone up 25mm, so you can go another 25mm in lift.
The 265/75/16 will be the more popular tyre, which means better pricing, and also better flex off road due to a greater sidewall height
All the best
Aaron
Hi, I have a 2011 Dmax with standard tyre 245/70/16. I am looking at going a bit bigger like 245/75/16 or 265/70/16. What would be the benefits of going either way. Ute is mainly used city driving with a bit of beach
TIA
Hi Greg,
Check this out – https://www.4wdingaustralia.com/4×4/fitting-bigger-tyres-to-your-4wd/
All the best
Aaron
I have a 2015 SX and was concerned as I wanted to upgrade to the 265/75 R16 (803mm) which is 54mm above the delivered spec.
I was advised to check inside the manual to see what tyres are listed and sure enough it has 245/70 R16 (749) and 255/65 R17 (763) listed for the High Ride.
I am getting the 265/75 R16 and if I am pulled over I will point to the owners manual and the 255/65 R17 (763) and state that I can go 50mm over this, the 275/75 R16 (803) is 10mm under this so it is legal in QLD.
Hey Daniel,
Cheers for that information; I never knew that it was mentioned in the manual
All the best
Aaron
Hi,
Does this mean that I can put a 285/75R16 tyre on a Landcruiser 76 Workmate? The Workmate comes standard with 225 tyres, but the GXL model (which I believe was only cosmetic changes) comes with 265.
Cheers
Hi Beau,
Possibly – jump on an online tyre calculator, put the sizes in and make sure its under 50mm increase. As long as its just cosmetic changes, you should be good to go.
I would recommend to confirm this in writing for your own peace of mind with your local authority
Aaron
Hi,
On the new dmax x-terrain the size is 265/60/18 ~ 30.5, if I am allowed to go 50mm high, that means I can go 32-33 inch tyres? mind you the tyres are already upgraded as much as possible I think ?
Thanks in advance
Hi Moin,
50mm from the largest tyre size in the range. You’ll have to find out what that is, convert it to metric, and then find a tyre size thats under 50mm increase
All the best
Aaron
Hey mate
I have a 2007 SR Toyota Hilux, I’m just wondering because the standard size for the SR is 205 R15 but for the same year SR5 version it’s 255/70 R15. Does this mean the 50mm clearance can apply to my car based off the SR5 or would I have to stick my original?
Hey Chevy,
Providing they are the same vehicle in terms of structure, driveline, suspension etc and its only cosmetic changes, yep, you can go off the largest tyre size in the range. If the SR5 has different suspension, or brakes, or anything that would change its handling then no, you can’t.
All the best
Aaron
Hi,
I have a 2015 BT50 with stock 17×8 rims and OEM size was 265/65/17. Largest tyres I have seen in this size is anywhere from 776mm to 790mm based on tyre manufacturers websites. My query is would I be able to go for a tyre with a OD less than 840mm being +50mm from the 790mm in the stock size? Reason I ask is that the online calculators only show OD sizes for the 265/65/17 from 776 to 777mm so there is quite a difference there in some tyre sizes.
Hi Adrian,
I would find the largest tyre size in the range and go to the tyre size calculator and pick something under 50mm larger than that. I guess you could argue that the tyre is actually under the size in physical form, but I suspect they will just calculate the tyre size off its designated size, not the actual size.
All the best
Aaron
So I’ve recently beefed up the suspension on my Dmax & it’s given me around 2inches of lift.
I currently have 265/65/17R tires on standard alloys. Could I go up to 275/65/17R?
Hey Aaron,
If you live in WA, you can only increase the roof height by 50mm from the tallest model in your range. If your suspension has already gone up 50mm then you are likely to not be able to increase the tyre size much, if at all.
All the best
Aaron
Hi Mate, cheers for all the useful information! I have a 2019 Dmax LSM,
will the 265/75/R16 fit without a suspension lift ? I can’t get a clear answer from anyone. Thanks
Hey Jacob,
Yep, they will. I ran them on mine for a while with no lift. This assumes you haven’t got a heap of weight on board and saggy springs, and that you keep the same offset rims, but it should be fine
All the best
Aaron
Hi Aaron. An informative article. I am struggling with tyre size for my PX3 XLT ranger in QLD and the 25mm height increase rule, but after reading this and it going off the largest tyre in the range I have a new question: Does the Ford Ranger range include the Raptor which uses a 285/70/17 tyre size?
Thanks again for the article.
Hi Simon,
I very much doubt it, as they run different suspension and drivelines. From an engineering perspective, if only cosmetic changes have been made (as in leather seats, DVD players, chrome door handles etc) there is no change to the way it would perform.
The Raptor is vastly different, hence its different tyre size
All the best
Aaron
just woundering what off set for 265/75.16 on 2018 dmax i am currently running 2245/70/16 i also have a 2inch lift many thanks
Hey Wayne,
I have no idea what the 2018 offset is, but if its the same as the previous models, it will be +33. It will be stamped on the rim somewhere. You can keep the same rims (+33), and it will fit just fine, or go slightly more negative (no more than +8 or it will be illegal) and it should still clear the guards. I wouldn’t change the offset if you can avoid it, as you’ll end up with rocks getting flicked out of the guards and damaging your paint work.
All the best
Aaron
Hi Aaron. I live in Perth and I am getting the 2021 LSU Dmax and intending on changing the 265/60 R18’s for 265/70 R17’s, 17″ x 8″? thinking about a +30? without a lift. I am pretty sure that’s going to work, would you know if this will cause any problems at all. I can’t find much information out there at the moment on these new models. The height difference is 28mm higher with the 17″ so legally should be ok. Thanks.
Regards
Russ
Hey Russell,
The tyres are 27.6mm bigger diameter, which means your vehicle will only go up by about 14mm. This should fit perfectly fine without a lift. I would verify that the 17 inch option is on the tyre placard inside your drivers door before you do it, but its a sensible tyre size change (providing they are a common tyre)
All the best
Aaron
Thanks for getting back to me Aaron much appreciated and thanks for the advice. I am not going to go to crazy with this ute just enough mods to get me were I want to go. Great website very informative.
Hey Russell,
You are very welcome mate. Enjoy the new vehicle!
Aaron
so ive got a n70 hilux with stock 225/75r16s and I want to put a 265/75r16. is this legal and will they fit the ute due to me not having a suspension or body lift
Hi Mike,
I have no idea mate. I’d suggest you jump on Redbook, find out the standard tyre sizes, then jump on a tyre calculator and see how much increase it is. From there, find out the maximum tyre size increase in your state from main roads, or the transport authority, and then lastly jump on Facebook to an N70 group and see if others are running the same tyres.
They probably will fit, but I don’t have any experience with that model Hilux
All the best
Aaron
Hey Aaron. I have just got a new generation 2021 MUX LSU badge. The standard tyres are 265/60 R18’s, which are Highway Terrain. I would like to replace with AT tyres however was wondering if you could help me out on the correct tyre size to get as much legal lift as possible? Thanks a lot, Cheers
Hi Josh,
Head to https://www.exploroz.com/Vehicle/Tyres/SizeCalc.aspx
Put your tyre size in, and you can go 50mm above that, unless there is an MUX model that runs a larger tyre (which there probably isn’t). You just need to look at the overall diameter size.
I would also speak to the tyre shops and get something that is common; it may require you to change rim sizes, if that’s something you would consider.
All the best
Aaron
Hi Aaron,
I’m waiting on my 2021 LS-M to arrive and know they come with the standard 255 / 65 R17 tire size ( all terrain ) but was wondering should I go bigger? I don’t intend to do a crazy amount of rocks and mud passings, mostly beach sand and probably a lot of corrugated gravel tracks up north from perth. Just wondering if you think the standard tire size is good enough or is your opinion to go bigger?
Cheers mate
Hi Tess,
Stick with the standard tyre size for now, and see if it limits you. A bit of extra clearance can be helpful, but also unnecessary depending on what you are doing with it.
The larger the tyre the more downsides you have – fuel economy, power, torque, worse braking, increased chance of breaking something and the list goes on and on.
All the best
Aaron
hi my ISUZU Vcross 2018 model INDIA has a present tyre size of 245 / 70 / R16
My question is can i go for a upsize of 275/ 70 / R16
also is it advisable for this upgrade, and do i have to undergo any alternations to my body, and will it effect my vehicles performance in any way. and will it have any effect on safety , speed and load bearing capacity.
Hi Sanjay,
I’m not familiar with a Vcross, nor the rules over there. You are talking about increasing the tyre diameter by just over 40mm, which is a pretty normal tyre size increase. You will have a higher centre of gravity, worse braking, use more fuel and I suppose possibly be less safe, but for all of these it won’t make a huge difference.
I suggest you read this – https://www.4wdingaustralia.com/4×4/fitting-bigger-tyres-to-your-4wd/
All the best
Aaron
Hi Aaron,
Just wanted to run a query by you. I have a 2016 Mazda BT50 which came standard with 265/65/17 tyres on 17×8 standard rims. I am based in Qld and according to the TMR the non standard modifications is based on LS section of the NCOP. I was wanting to check as in section 4.1 of the LS section is states: 4.1 REPLACEMENT TYRES ON STANDARD (OR MANUFACTURER’S OPTIONAL) RIMS
Some tyre sizes have become obsolete and are no longer available. Equivalent replacement
tyres with different size designations may be fitted without specific certification under this
Section.
Does this mean that if I stick to the OEM rims, I can fit any size tyre as long as it complies with load rating requirements etc and is inside the guards?
I understand that the TMR guidelines state 50mm OD increase but find it very odd about this little statement if you wanted to keep the OEM rims.
Hey Jon,
I think you’ll find it means you can run tyre sizes that aren’t on the placard, not that you can install any tyres you want to run.
More than likely you’ll still be under the 50mm increase arrangements, but the only way to know for sure is to get it in writing from the TMR.
All the best
Aaron
Hi Aaron,
Do you think rim size has any impact on this?
My base LS Colorado is R16 (245/70), the higher spec LTZ is R17(255/65) – overall the higher spec is 14mm larger diameter, so 7mm higher car height.
Hopefully then that will offset some of my larger tyre size (265/70/R16 – 28mm diameter over LS standard size/14mm height) = only 7mm higher, and allow a 40mm lift+GVM upgrade all legally.
Does that sound right to you? (I know your not a DoT engineer 🙂 )
Thanks
James
Hi James,
Rim size is irrelevant. Only the tyre OD matters in this regard.
If the higher model has no driveline/suspension/chassis changes you should be able to go 50mm bigger than the OD of the tyres on that model.
265/70/16’s are 777.4mm OD, and 255/65/17’s are 763.3mm OD, giving an increase of 7mm in height.
All the best
Aaron
All the best
Aaron
Great article … exactly what I was looking for, so thanks!
In one of your comments you say “I swap between the tyres a fair bit. I can’t feel any obvious differences, but it does brake worse, get marginally worse economy and you do lose some power and torque” … that ‘marginally worse economy’ – is that based on odometer readings or real distance?
Let’s say (with the original tyres) you reset your trip-meter and drive 100km to get your new tyres fitted.
You then reset the trip-meter and drive back … as your new tyres are 7% larger your trip-meter would only read 93km.
If the Dmax drank 10 litres on the way to get your tyres fitted and 10 litres on the way back, the consumption is the same … but if you make the calculations using the trip-meter it would look like the Dmax consumed 7% more on the way back.
Hey J Nik,
My understanding is that the speedometer on the Dmax is out by 7% from the factory, but the odometer is not. I haven’t actually verified this, but on our fuel calculations we add 7% distance so we are getting the correct litres per 100km
All the best
Aaron
hi mate – i emailed RTA here in NSW and they stated that the 7% applies to the size on the tyre placard. wonder why its different interpretation in WA?
cheers
Hey Mungoman,
It doesn’t surprise me at all; the states all vary in the way they approach 4WD modifications. At the end of the day all you can go off is the information relevant to your state
All the best
Aaron
Hi. I have a 2017 dmax 4×4 with 255/65 ×17 tyres
Could i replace with 265/60 ×18 wheels
Thanks Rob
Hi Robin,
Possibly, although I wouldn’t go up wheel size. You’ll have to check the dimensions, and then see what is legal in your state, and make a decision from that.
All the best
Aaron
I don’t think it’s 50mm bigger than any vehicle in the model range. It’s ‘your vehicle’ so it just goes by the tyre placard on the car. In fact, it’s 2 inches, which is 50.8mm.
Hi Howie,
The ADR’s are quite clear (and quoted in the article, word for word); it specifically says 50mm, and not two inches, and it says that vehicle, not your vehicle. It makes sense that the OEM brings out a range of different models, with the same design except for cosmetics, and that they are engineered to suit the largest tyre run in that range.
If you had an SX Dmax, and an LSU Dmax, they are identical minus cosmetic changes, so you can go the 50mm increase off the largest tyre size run in that model. As soon as you start playing with brakes, or suspension, or chassis length etc, then its not compatible; you can’t compare a Ford Ranger to a Ford Raptor, as they are vastly different.
All the best
Aaron