For those not sure...31" tyres are legal on new hilux.

[Hilux Max]

Guys,

was doing some research on the Vicroads website, and thought Id find out if 31" tyres were legal or not as some of the forum members are concerned that they may not be given the +15mm diamter increase rule over stock.

So heres what i have found.......

According to Vicroads Vehicle Standards Information - May 2003 Guide to vehicle Modifications it states the following-

The overall diamter of any replacement wheel & tyre must not be:
- more than 15mm greater than largest diameter tyre specified by the vehicle manufacturer for that model or vehicle series.

Therefore, the largest wheel and tyre combo in "the series" as quoted is the TRD Hilux's 265/65x17, which when worked out on that size equates to 77.63cm or 30.56 inches diamter.

So if we add 15mm to that size we get 79.13 or 31.15 inches diameter......see? it's legal!

In regards to increase track width, you can only only increase it by 25mm, so if we have the SR5 as the standard with a +30mm offset, then we can increase it by 12.5mm per side, which mean we legally cannot run a bigger (read space out further) offset than a +17.5mm.

hopefully that helps, now all you have to do is find a 31" tyre that fits the load rating requirements.

[Quinny34]

And have you found a 31 that meets these specs..... Im about to get new rims and tyres for the new lux so keen as dogs sh!! to get it right first time round...

[rodw]

As the 15mm rule also applies in QLD, 31" tyres are also legal in this state too!

[biglux]

Maxxx,

I take it that the TRD and the SR5 are both the same except for the fruit. Because the trd has bigger wheels fitted would that mean that the sr5 can have the same size tryes legally?? I'm having trouble with making up my mind on a new set of wheels and tryes, and don't want to void my insurance. We have the same 15mm bigger rule up here in QLD.

The standard OD trye for the sr5 is 29" and the trye dealer i have spoken to about a set of Mickey Thompsons says that the only legal size i can go is 245/75 R15 which works out to be 29.5" (10mm bigger). I would like to go to the 31" tryes but don't know which is legal and which isn't when comes down to the crunch ie.claim time with insurance.

[Hilux Max]

mate, its all explained in me first post...you can go +15mm over the largest tyre diamter available for the series of vehicle....which is the TRD, having a total diamter of 30.56 inches in 265/65x17 +15mm which is just over 31"

Im currently sussing out also the front axle hub and bearing specifications.....

Hilux and Prado are interchangeable because they are similar but the axle hubs have a different part number.....when compared to the 200 series , the axle hubs between the prado and 200 series look identical other than the 5 stud or 6 stud setup.

therefore, if you include the +15mm rule over the 200 series in theory and if you had all the hubs infront of you to test properly, you may be able to justify just over 32" tyres legally to an engineer on the hilux...

33" if some of them consider the +50mm rule that there is still some confusion over.

Like I said, expensive excercise to get all three hubs and test the load ratings amongst them...just something to think about that was raised on Outerlimits in a discussion regarding 35's and engineering.

anyway, Im thinking out loud again, and those voices are starting tot alk to me....LOL

[rodw]

Biglux,

The Qld bible is a bit vague on hte top of page 11 on this link http://www.transport.qld.gov.au/resourc ... icles2.pdf

where it says "The rim diameter may be varied from the standard size but the overall diameter of the tyre must not vary by more than +15mm or -26mm."

So you can change the rim diameter, but it says nothing about the tyre being for the same model vehicle (read carefully above, tyre size is not tied to the "standard size")

Vague is good as nobody (not even the regulators) really know what is going on. Go with a specialist 4WD trye shop and they will know what they can get away with. Fourbys told me 31" tyres were legal and I beleived them. Everybody is still trying to convice me they are illegal on this forum and my mates thought they were standard size tyres.

Insurance will be the last problem you will have. I totalled a car wearing Swampers on the highway (which have questionable legality to say the least) and nobody (police or insurer) cared. If it is not cut and dried, the insurers won't take you on.

[Hilux Max]

Insurance will be the last problem you will have. I totalled a car wearing Swampers on the highway (which have questionable legality to say the least) and nobody (police or insurer) cared. If it is not cut and dried, the insurers won't take you on.

I think that pretty much says it all...insurance companies have been in the game for a while and if they were suspicious about any modification,they wouldnt be taking the risk of insuring you.

theyd straight out reject you or ask for the vehicle be inspected before deciding.

so going by your exprience rod, are you saying swampers are road legal?.....LOL

just kidding.

[rodw]

so going by your exprience rod, are you saying swampers are road legal?.....LOL

Must be mate because nobody said they weren't legal but one of the fireys who attended the scene was head to say that lack of grip certainly was not the cause of the accident as he surveyed the furrows they dug under full lock before I hit that tree with no steering!

[biglux]

Thanks for that fellas, i'll be going the 31" option
Much appreciated

[wat700]

Interesting....

I spoke to the RTA in NSW about their wording:

Minor changes to wheels

Wheels up to 26mm wider than the largest optional wheel recommended by the vehicle manufacturer for the

vehicle can be fitted without the need to notify the RTA.



The outside diameter of the wheel and tyre combination must be no more than 15mm over the largest diameter

wheel and tyre combination specified for the vehicle and not more than 15mm below the smallest diameter wheel

and tyre combination specified for the vehicle.

And they gave me the following response:

It means that particular model,as outlined by the tyre and rim placard,which is fitted by the manufacturer.

RTA Tech Enq

So according to the RTA, in NSW at least, you can only go 15mm above the size of your original tyres fitted to your particular model (ie SR, SR5, TRD).

Hopefully I'll get posted out of NSW at the end of the year and be able to fit some bigger tyres legally!

Cheers,

Watto

[Hilux Max]

just do it Watto...you know you want to.....

[wat700]

Maxx don't tempt me!!!

I really do want to!

[rodw]

I'm with Max, just do it!

[jackolux]

Shyte now I'm really confused

[Joe072]

Fellas,

I've been doing this reasearch over here in Perth for the last 2 weeks. Tyre power have advised me that I can legally go 50mm greater overall in diameter than original spec with no probs. I wanted 265/70/17 but they are 65mm bigger so the 265/65/17 (same as stock Prado) are the go as they are 38 ish mm bigger. I have attached a link to VSB14 - section 11 which is the national code of practice for the modification of vehicals - suspension section etc which covers tyres. It seems a lot of you may be getting info relating to passenger cars and not commercial / off road cars. Read the info on page 16. Our Hilux's are commercial vehicals therefore the 50mm rule should apply ???????
I did also ask Toyota about the TRD and whether it had suspension and brake upgrades from the SR5's. They have said yes, therefore the actual stock size wheels on the TRD - 265/65/17 I don't think are able to be a base for us to go 50mm greater than those.
It all comes down to insurance and what they may do if your have greater diameter than recommended.
Thats my 2c worth and I hope it is helpful.

http://www.infrastructure.gov.au/roads/ ... eb2006.pdf

PS - BFG's just come out with the 265/65/17 AT's so I'm sold.

[rodw]

Joe, but the NCOP has not been adopted by all states yet so you have to go with the present rules and that is where Max and I have focussed on (in VIC and QLD). If WA has adopted the NCOP you are good to go. QLD was to adopt it in early 2009 but decisions were delayed. Maybe after the election later in the year we will adopt the NCOP.

[Joe072]

My mistake - you'd think "national' meant all states, but as usual the left doesn't talk to the right all of the time. Well hopefully they adopt it soon so that all of us are on the same page so to speak.

[Blue]

For Victorians - I just purchased BFG AT's for the Triton in 265/65R17 - it's a lease vehicle and the tyre retailer has to get authority to fit them - phone call to Leaseplan resulted in words to this effect: "Allianz underwrite our insurance and they are satisfied that 265/65R17's fit within the 50mm allowance in the NCOP"

Yep, they actually quoted from the NCOP...

[Hilux Max]

change insurance companies blue, and dont tell the lease company what tyres are on it.

as long as insurance covers whats on your vehicle, all the lease company needs to know is the expenses you spend on mainting and servicing it, and the kilometres travelled.

[Blue]

change insurance companies blue, and dont tell the lease company what tyres are on it.

as long as insurance covers whats on your vehicle, all the lease company needs to know is the expenses you spend on mainting and servicing it, and the kilometres travelled.

I think you missed the point, the insurance referred to the NCOP (50mm allowable) instead of VicRoads (15mm allowable) so it was a win for me...

LeasePlan need to know everything mate and I mean EVERYTHING...!!! They have to be consulted and give approval before you fart on the factory trim... I would opt for a different leasing company but I simply couldn't beat the overall savings - it's worth the hassle, especially the fuel savings - currently paying under 90c/L for diesel...