Thread: 245/75/16 illegal?wtf

Originally Posted by pawl

Just been priceing tyres and decided to go up from the stockies(235/70/16) to 245/75/16 and the tyre manager told me going up by more than 15mm will make my disco illegal, as the increase was approx 40mm. Is this true? I thought it was a limit of 2 inches increase in diameter. He was trying to convince me to go down to 225/75/16, the guy obviously has no idea why we need an increase in height. But is the 15mm limit true?????

Yes...but a lot of people choose to ignore it.

I have my car engineered with 245/75/16's on

Here's the stats on the 2 tyres:

Stock Tire >Search Tires Tire 1 - 235/70R16 >Search Tires Tire 2 - 245/75R16 >Search Tires
Section Width:--Section Width:9.25 in235 mmSection Width:9.64 in245 mmRim
Diameter:--Rim Diameter:16 in406.4 mmRim Diameter:16 in406.4 mm
Rim Width Range:Rim Width Range:6 - 7.5 inRim Width Range:6.5 - 7.5 in
Overall Diameter:--Overall Diameter:28.95 in735.33 mmOverall Diameter:30.46 in773.68 mm
Sidewall Height:--Sidewall Height:6.47 in164.33 mmSidewall Height:7.23 in183.64 mm
Radius:--Radius:14.47 in367.53 mmRadius:15.23 in386.84 mm
Circumference:--Circumference:90.94 in2309.8 mmCircumference:95.69 in2430.5 mm
Revs per Mile:-Revs per Mile:718.4Revs per Mile:682.8

38mm difference in diameter....... = 19mm lift

yep, by the newer regs

you can have 150mm lift total (without having to jump a stupid number of hoops)

50mm from suspesion mods
50mm from tyres
50mm from body lift.

heres the kicker the older regs on tyres are roughly thusly

your allowed an inch over or under (more or less) in the rolling DIAMETER of the tyre before you're supposed to get it engineered but you can go to as wide or a skinny version of the right diameter tyre as will legally fit on your standard rims providing it doesnt also go outside of your guards or fail to meet max speed or load rate of the vehicle.

they havent redone the criteria in any major way for tyres yet but I reckon they're thinking about it.

I am not sure about ohter states however QLD legislation is as follows (supplied by the Department of Transport);

The speed rating of all tyres must be:
a speed of at least
for an off-road passenger vehicle - 140km/h

Load ratings of tyres must be at least equal to the minimum specified by the manufacturer on the tyre placard fitted to vehicles made after 1972.

Tyres can be up to 1.5 times the width of the manufacturers widest option as long as wheel track is not increased by more than 50mm and tyres are within guards / flares.

Tyres width can never be less than narrowest manufacturer tyre.

In QLD tyre size also can not be increased by more than 15mm over manufacturers maximum tyre size on placard.

After looking at this information, the only option for a taller tyre for my D2 is a 245/70/R16 at 750mm diameter (12mm larger than std.)

Unfortunately as the min. width tyre on the placard for my vehicle is a 235 I can not go down to a 225/75/R16 either.

There is not much available in an agressive tyre for a D2 that is legal in QLD.

There was a "poverty" pack Disco released with steel rims instead of alloys.

Might be worth seeing what tyres were fitted by LR. They're bound to have been narrower than the alloys.

mine had steelies, and what i assume might have been the original size tyre, they were 205/80/R16, IMO undersized for the disco
im now running 235/85's stuff the rules, who's seriously gonna book you?

The original D2 steel rims are still the same size as the alloys at 16x7 (the alloys also came in 16x8 and 18x8).

Original tyres for the steel rims were either 215/75R16 or the same as the 16x7 alloys at 235/70R16.

Edit: Whoops sorry thought I was in the D2 area!

I've got Coopers ATR 255/70/R16 and just had a roadworthy.
Placard says max on 8JJ rims 255/65/R16.