Fitting bigger tyres to your 4WD; what should you consider?

One of the most common modifications done to a 4WD is to fit bigger tyres to it. This is done for a number of reasons, but the primary one is to gain more clearance. You won’t get far with the bottom of your 4WD dragging on the ground.

A lift kit will pick your chassis and body up, but the lowest point of your vehicle is always going to be your differential (except on independent suspension vehicles or those with portal axles).

Contrary to popular belief, a lift does not give you more clearance. The only way to gain true clearance is to install bigger tyres.

However, know that even if you can, and do bolt on larger tyres there’s a lot more to it. Everything comes at a cost, and installing larger tyres to your 4WD is no different.

If you want to know ‘Can I put bigger tyres on my car?’ this post covers everything you want to know, from the legalities to benefits and downsides and everything in between.

80 series 285/75/16
50mm diameter bigger tyres on our 80

Why fit bigger tyres?

There are a few benefits of increasing tyre size, which I will go into below. Remember though, there are downsides of 4WD accessories and modifications; don’t forget about them.

Some of them can include voiding your insurance if your vehicle isn’t legal, not mention terrible handling too.

Consider the 32 ways to make your 4WD illegal before you change anything, as the risks are significant and this is very, very important.

Tyre size is important
Why fit bigger tyres?

More clearance

I mentioned above; the only way to truly gain more clearance in your 4WD is to install bigger tyres. Actually, I lie; you could install a set of portal diffs from Mark’s adaptors, but they are extremely expensive and out of the large majority of people’s budget.

If you add 4WD tyres that are 1 inch, or 25mm bigger in diameter, the height of your vehicle goes up by 1/2″ or 12.5mm. This is important; know that your vehicle only goes up by the radius, not the diameters difference.

Most people go for 1 or 2″ bigger tyres, giving you 12.5mm or 25mm of additional clearance. It’s not much, is it?!

More clearance is great off road
Clearance is a game changer off road

Better traction

By changing tyre size up, more rubber is in contact with the ground. This results in greater traction, as well as greater flotation. This is why vehicles with taller tyres perform well on the beach. More surface area touching the sand means you have less weight per given area, and thus less chance of sinking!

Greater traction off road
Bigger rubber means more traction

Tougher looking vehicle

I nearly didn’t put this on the list, but the reality is, some people really care about this. A 4WD that has one or two size tyres up looks better.

If this is what you are doing the mod for though, I’d suggest you skip it; just get a set of muddies, or a new set of rims! I prefer function over form, but not everyone agrees with this!

Bigger tyres on a 4WD
Aftermarket rims and bigger tyres certainly look better

How much difference does it really make?

Lets look at this from a number of perspectives. For every 25mm bigger overall diameter tyre size increase, your vehicle only gains 12.5mm of extra clearance. Say you go from 31″ tyres to 33″ tyres, you will gain 25mm.

Does that 25mm really make much difference? Some say it does, and some say it doesn’t.

I would say the right Tyre pressures and tread pattern would make more difference. If you go up more, from 31″ tyres to 35″ tyres, you gain 50mm clearance. This is quite a bit more, but again, nothing that Lockers wouldn’t make up for.

31 inch tyres on a 22R Hilux
Our Hilux with 31 inch tyres
33 inch tyres on the lux
With 33 inch tyres

It’s interesting to look at the drag marks left by 4WD’s when out on a 4WD track; check it out next time you go off road. It gives you a good indication of whether your tyres are too small for the terrain.

There’s nothing wrong with dragging a diff slowly and carefully over terrain on the odd occasion, but you don’t want to smash it up against anything. This is where diff guards come into their own.

What about the 4WD you have?

This is the factor that makes all the difference. Take a 1990 model Toyota Hilux, and compare its clearance to that of a 2010+ version. They are chalk and cheese. Older vehicles, with solid axles tend to have more clearance from the factory than modern vehicles.

Does this then suggest that you don’t need to go up size tyres? Perhaps; it all depends on what you use the vehicle for!

Limited clearance
Our new Dmax has much less clearance than the previous 80 series

How big are your diffs?

When I had my Hilux, I compared the clearance from the ground to the lowest point to that of a GQ Patrol. The Hilux had about 25mm extra clearance right from the get go, purely because it had smaller differentials hanging down.

Being oversprung too, they have a huge amount of additional chassis and body clearance over a GQ Patrol. Oversprung refers to the springs sitting on top of the differential, instead of undersprung, where they are under the differential (and hurt your clearance quite badly).

The point I am making is it very much depends on your vehicle, and where you drive as to whether the bigger tyres are worth it.

Differential size
The size of your differential is directly related to clearance

Are you allowed to run bigger tyres?

Please, please don’t skip this. You are responsible for driving a vehicle on the road that is safe, and legal on the road. Despite this, many people choose to ignore what the law says, and run what ever tyre size they want.

You can’t legally do this, and the ramifications are very, very serious. Ignorance is not an excuse either. 4WD tyre sizes are heavily regulated, and often in combination with suspension and body lifts.

I’m not talking about a slap on the wrist and a yellow sticker from the local policeman, I’m talking about potential jail time and mammoth medical bills to pay if your proved to have been driving an unsafe vehicle, or if your insurance company finds out and just walks away, leaving you to sort it out.

Rolled 4x4
If you have an accident with bigger, illegal tyres it can be a major problem

In WA, you are limited to a maximum of 50mm bigger diameter increase. However, this is just the beginning. If you go up 50mm in diameter, you have lifted your vehicle 25mm and as a result are only allowed to install a 1 inch lift kit (or have the roof height go up by 25mm further).

The total height that your vehicle goes up in WA must not exceed 50mm, unless you get engineers approval. This includes tyres, suspension lifts and body lifts. You can find out more about this at Is your 4WD legal?

The only exception to running tyres bigger than a 50mm increase on your 4WD without engineering is if there is a different model 4WD in the same year range as yours that comes from the factory with larger tyres, and has exactly the same setup, just cosmetic differences.

You can read about this here – Can you go more than 50mm diameter increase with 4WD Tyres?

If you are looking for a legal tyre size calculator, you won’t find one as it varies from state to state. Instead, find out what your local regulations are and go from there.

Touring Australia with lots of gear
Do you know what the maximum tyre size is for your 4WD?

Are wider tyres better?

This is a can of worms. One that I am loathe to touch on, but I will anyway! When you see 3 tonne Land cruisers just idling down a super soft beach on the factory skinnies (or cheese cutters) it gives you an indication of the capability of a tall, skinny tyre.

Rearranged Rover at Lancelin
Too wide?

On the other hand, a 10.5 or 12.5″ wide tyre also does extremely well off road. Personally, I wouldn’t go wider than this. Remember that your traction and floatation come primarily from the length of the surface area touching the ground, not the width.

Wide tyres might seem like they would spread the load even more, but then you have to bulldoze sand, mud, snow etc out of the way, just so your tyre can continue moving.

This is very much a personal thing, depending on your driving conditions and requirements. To me though, there’s not much point going over 12.5″ wide.

Skinny tyres
Why do so many 4WD’s run skinny tyres? They can’t be that bad!

What are the disadvantages of bigger tyres?

I will start off by stating our 80 Series Land Cruiser has 285/75/16″ tyres on it. This is one size up, and gives us a small amount of extra clearance.

I could have gone bigger tyres, but there are many, many reasons I didn’t. There are plenty of negatives to fitting bigger tyres on your 4WD, which I will go into below.

Speedometer inaccuracy

The most important thing to know when you get in a 4WD with different tyres is that the speedometer may not be accurate. If you purchase a second hand 4WD and the owner doesn’t tell you about it, you run the risk of getting a fine, or worse!

Your speedometer, trip meter and odometer will be out by the percentage of size increase. If your diameter increases by 50mm (31″ to 33″ or 33″ to 35″) your speedometer will be out by roughly 10%. This varies considerably from car to car, but its something to pay attention to.

By law, your speedo can only be out by 10% (seems a bit ridiculous that new cars can come out with 10% variation), but its something to be aware of.

This also messes with your fuel economy calculations. You can still work it out; have a read of this – How to accurately work out your 4WD’s fuel economy.

Speed with bigger tyres
Bigger tyres will throw your speedometer and odometer out

Less power and torque

The tyres on your 4WD are essentially the last gear in your gear train. It’s not too different to changing a sprocket in a chain drive; the output power and torque will change. By fitting larger tyres, your vehicle will do less revolutions per kilometer, but it has to work harder to do so.

Again, this is very much vehicle dependent, but for most vehicles there will be a noticeable difference in power and torque. In a diesel 4WD, sometimes this is less obvious as they seem to just tractor along, but it is evident.

My 2.4 petrol Hilux used to lose a substantial amount of power every time I threw the 33’s on.

The 80 series turbo diesel loses a bit of power and torque, but its not as obvious.

The easiest and most accurate way to see what difference has been made by changing tyre sizes is to check via an EGT (Exhaust Gas Temperature) gauge.

A bigger tyre makes your engine work harder, and this translates into hotter exhaust temperatures. Our 80 series went up by roughly 20 degrees throughout the range when we installed the larger tyres.

Bigger tyres hurt power
Running bigger tyres eats into your torque and power

Decreased braking

Possibly the primary reason for restrictions on fitting bigger tyres is the reduced braking capacity. As the tyre diameter increases, your braking capacity decreases.

This is a serious concern; your brakes need to work as well as possible. So long as you stick within the legal requirements of your state though, you won’t have an issue.

Braking efficiency decrease
The bigger the tyres, the worse your braking

Increased stress on your driveline

Everything that indirectly attaches to your tyres is put under more stress when you fit bigger tyres. This includes your CV’s, steering box, steering shafts, axles and differentials.

Many people will not break components on standard tyres (especially CV’s) but as soon as they go up a few tyre sizes the breakages happen on a regular basis.

Increased fuel consumption

Some people will argue with me here, saying it makes no difference. It may make very little difference if you are fortunate (generally the vehicles with plenty of power), but if your engine has to work harder to turn the new wheels you are going to use more fuel.

When you work out your fuel economy, be sure to factor in the tyre size difference. If you do 90km on the trip meter, and your tyres are 10% bigger, you’ve actually done 99km.

My Hilux went up at least a few litres per hundred kilometers, which was expected because the poor engine was already working hard as it was. The difference in our 80 series is slightly less noticeable, and I think at 100km/h it actually uses less fuel do to the revs being more centered in the torque curve.

Please don’t fit bigger tyres without accepting the risk that your fuel economy may get worse!

Our 80 with 265 tyres
Our 80 the day after we bought it
Bigger tyres on our 80
Upgraded to 285/75/16 tyres

Legal ramifications

You know those yellow stickers that get handed out regularly, which basically say your vehicle is not roadworthy? Bigger tyres are one of the easiest ways to attract attention to your 4WD, and are often the reason for yellow stickers given to 4WD’s.

However, a yellow sticker is the least of your worries. If you are driving a vehicle that is not compliant with the local regulations, your insurance company can walk away from any claim you make. If you rear end a Ferrari, or you seriously injure yourself, you could end up with a massive bill that you have to pay.

Even worse, if you are found to have caused an accident that injures (or kills) someone because of the bigger tyres (or other illegal modifications) you could even go to jail. It’s not worth it – do things by the book!

Potential scrubbing

There is a reason that 4WD’s come out with the tyre size that they do. You might be able to fit the next size tyres on your 4WD, but go a couple of sizes up and things will start to get tight. The first thing you will notice is that the tyres foul on the inner guards (usually at the front) or the bull bar.

If it is only minor scrubbing you may be able to get away with it, but remember to consider when the suspension flexes upwards it will move closer to your guards. The only way to fix this is to modify the 4WD, which isn’t impossible, but its a steep slope that is hard to stop yourself on in both time and money.

Gateway to more modifications

Bigger tyres usually result in further modifications. People find they aren’t happy with the power difference, and start looking for mods to make their vehicle make more power. If the tyres don’t fit properly, the next step is suspension or body lifts, or to trim the guards.

Believe me; once you start this slippery slide of 4WD modifications, there is no getting off! I don’t say this to put you off installing bigger tyres, just to make you aware of the potential expenses down the track!

80 series land cruiser build
Before you know it, you’ve modified everything!

Higher centre of gravity

The ultimate 4WD has a low centre of gravity, and plenty of clearance. For every size tyre that you go up, your centre of gravity also goes up, making it more likely for your vehicle to roll if something was to go wrong.

Center of gravity on a 4WD
A higher center of gravity isn’t a good thing

Warranty issues

The moment you run larger tyres, you open a window for warranty problems. A lot of 4WD manufacturers will decline any driveline warranty claims based on running larger tyres, so watch out. There are cases where aftermarket accessories void your warranty, and bigger tyres are a common cause.

Alternatives to fitting bigger tyres

Ultimately, bigger tyres are fitted to make a 4WD more capable. The thing is though, there are many ways you can do this. For example, a locker will make your vehicle immensely more capable. If the decision came to it, I’d keep my vehicle legal and install a locker instead.

Having installed ELockers not too long ago, I know they have made our 80 series a lot more capable than the tyres ever did.

Wellington Dam 4WD Tracks
Differential ELockers!

Another alternative is to change the tread pattern. Muddies will give you significantly better traction than road or all terrains. However, match the terrain you drive on the most to the tyres you buy.

As always though, this all comes down to your individual circumstances. Where you drive, how often you drive, how far you want to go etc!

What size tyres should you run then?

4WD tyre sizes vary considerably depending on the vehicle you own, and the wheels it came with. There is no legal tyre size calculator, asides from doing your own research into what comes as factory, and then looking at the local law and going from there.

That said, the tyre size you end up with should suit your driving. A 6 inch lift and 35 inch tyres might look good, but it’s not really suitable for touring around Australia. How often do you need bigger tyres? Could you get away with something else?

I usually suggest one or two sizes bigger than factory (if this is legal) with some decent tread. This is either All terrains, or Mud terrains. Not sure what to get? Check this out – All terrain tyres vs mud terrain tyres.

Above all, stick within the legalities; its not worth the risk.

Looking for something else to read? Have a look at 42 things you must know about 4WDing.

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  1. Hey Aaron,

    Thanks for sharing mate, appreciate it.
    What tyres are you running on your DMAX? I have one the same and looking to upgrade the rubber.


  2. Hey mate,

    No problem. Pro’s and con’s to which ever way you go.

    All the best

  3. Thanks, a very impressive article, I do not intend to drive Perth to Cairns in a straight line so – I’ll keep it stock.

  4. Hey Jake,

    Unless you have a really good reason for running the larger tyres, I’d go with 265/75/16’s. They are marginally bigger than factory, very common and about the cheapest size you can get.

    I would look at other brands too – Toyo’s are good, as are some of the Nitto’s etc.

    All the best

  5. G’day Aaron,
    I like reading your articles, cheers for taking the time to help inform us less knowledgeable four wheelers. I too own an 80 series, but with the 1FZ-FE (petrol) engine and 5 speed manual. The previous owner had spent big on OE sized BFGoodrich all-terrains in 275/70R16 fitted to the factory alloys and I’m due to change them soon, but tyre choices in this size is limited; the BFG’s in this size are stupid expensive and I’m not sure if I want to go up to 285/75R16 because I’m worried about power loss, fuel consumption and braking. Do you reckon it would be that noticeable? What about 265/75R16s instead?

  6. Hey Adrian,

    You’d have to find out what the largest tyre size is in your model of Hilux, without any other mods to support them. I would say not all of the Hilux’s came with cheese cutters, although sometimes they are actually taller than the wider tyres a lot of people fit. Your maximum height increase will be 50mm on roof height from the biggest tyre size’d Hilux that exists. Whether you use that 50mm to fit 50mm bigger tyres (so up 25mm) or you just stick with that tyre size and go 50mm lift is up to you.

    The other thing to do is find out your actual lift height – a 2 inch lift that is a few years old might not be anywhere near 2 inches tall. There is a database, which I can’t remember the link to that will give you the information, but redbook or Toyota is a good place to start

    All the best

  7. G’day Aaron,
    Its been great reading the articles you have written about the legalities of raising the ride height of a vehicle through suspension and tyre size but it seems the more i learn the more i get bogged down, especially with the differences between variants of the same model car being thrown in to the mix eg. SR vs SR5.

    I am on a similar path to Sam back in June 2018 regarding ride height changes for my recently purchased 2013 SR hilux. This vehicle has a 2 inch lift kit installed but is still sitting on the stock 205/R16’s. What i have noticed as one of the most common upgrades on any SR hilux on WA roads in a 2 inch lift and the immediate replacement of the stock cheescutters to something larger like a 265/65/17. Going off all i have read so far this would make just about every one of these cars illegal?

    In a nutshell as my vehicle has got the 50mm lift kit installed already am i no longer able to increase the tyre size above what it is currently running? Or because the tyres on the model i am driving are smaller than the upgraded SR5 that can have 265/65/17s as stock am i still able to get some taller tyres?
    Thanks in advance!

  8. Hey Chris,

    I wanted more clearance. The only way to do that is to fit larger tyres. There’s no perfect setup though – bigger tyres use more fuel, cost you power and torque etc.

    I would only fit bigger tyres if you can do it legally


  9. Hey MAtt
    Why did you change tyres?
    Im looking at new tyres and in 2 minds whether to stay with the 245 or go to 265

  10. Hey Matt,

    I would stick with a common tyre size. There is some method in the thought that a tall, relatively narrow tyre is better, but don’t get something obscure. 265/75/16 is a common tyre size – go for something like that


  11. Hi All
    Can’t believe this thread is still going!!

    I’ve got a 93 4runner 3.0 VZE thats running 205/R16/LT. I’m wanting to go bigger and was considering a wider & taller tyre (275/70/16) or something but had a guy try and convince me that a narrower/taller tyre would be better (approx 225). I’m still sure that wider would be better but I’m already pretty sluggish in the old gal. Maybe he’s right? Thoughts?

    Probably looking for an AT as I go off-road maybe 20-30 times a year on sand and pea gravel out of Perth.



  12. Hey Adam,

    You are very welcome. By the looks of it the two tyre sizes are pretty much identical. The only difference then, is the rims. I would say you’ve probably gone wider, and a different offset. Do the tyres stick out or in further than they used to? If so, you may find this is why they are touching more than they used to. You can measure this.

    All the best

  13. Hi Aaron,
    Really informative page here! Thanks very much.

    I have a 2009 Hilux SR5 dual cab pickup. It had 17″ Prado alloys fitted at the factory and ran 265/70/R17 Cooper ST MAXX. I’ve just had the wheels replaced with Sunraysia 16×8 rims and tyres replaced with Mickey Thompson Baja ATZ P3s 265/75/R16.

    I get quite bad scraping of the front tyres at full lock on the mudflaps. I was told these tyres/wheels would be fine. So I was wondering what could be causing the scraping? I don’t know what offset the old wheels were, or what the offset for the new ones are.

    Any ideas?


  14. Hey mate,

    They are only 26.5mm diameter bigger, so not a massive change. You will notice a minor power decrease, and your fuel consumption will go up a little. This is partly due to the larger size making the engine work harder, but also because the new tyres will be more aggressive (assuming you are coming from the factory tyres) and less aerodynamic.

    On the flip side, you gain 13mm clearance. Give it a whirl; you might not notice too much of an issue.

    I would recommend you make sure you are under your GVM, GCM and axle loads (have a read of this –×4/a-simple-towing-guide-for-keeping-your-4wd-and-trailer-weight-compliant/) and if its an auto consider a transmission cooler

    Best of luck

  15. Hi Aaron,
    I have a 2017 BT-50 towing a 3+ tonne caravan. The original tyres are 265 65 17s. I would like to get a little more clearance for 4wd ing and have ordered some BFG 265 70 17s but I’m starting to worry about loss of power with the bigger tyres. At the moment the Mazda is pulling the big van well but it must be already near its limits. What do you think? I don’t want to risk a great towing set up for a little more clearance.

  16. Thanks Aaron, not going with splits again, have been looking out for second hand steel rims, will go for the Sunraysias as they look like a good rim
    Cheers and thanks for all you do, now if only I could find someone here in WA to fir auto lokkers lol

  17. Hey Wazza,

    Most people go for the Sunraiser type rim, but if you can find a suitable second hand set its usually the way to go. If you want to stay with the splits, I wouldn’t know where to point you to, other than the usual tyre shops


  18. Love the content and knowledge
    Had some new tyres fitted R05 R18C on 16,550 rims, which are split, tyre place said I need to get rid of them as the splits are getting like me, OLD and need replacing, in WA, and it gets confusing what rims etc to buy for those tyres
    Any rims you can recommend without costing an arm and a leg? Hilux LN167 1997 dual cab 4×4
    Thanks in advance

  19. Hi Bogdan,

    Sounds like a question for a tyre shop to me. The fronts are slightly less wide rim that sticks out 3mm less. The difference would be negligible


  20. Hi Joshua,

    The 265/75/16s are 28mm bigger. If the tyres come within 14mm of the guard they will touch. Also make sure the offset of the rims is the same.