Thread: Larger Tyre Issues

Originally Posted by chuck

Has anyone had any issues with fitting larger tyres to their D3 relating but not limited to the following;
1. warranty
2. traction control
3. dynamic stability control
4. fuel economy
5. fit

I am contemplating 265 x 70 x 17 - 31.6".

Thanks

Chuck

I fitted COOPER STT's to steel 17x8" rims. They are about 14mm bigger in diameter as they are 245/70 not 235/70 as are the standard tyres. They put the fuel consumption up by 1-1.5ltrs/100km, probably because of the lumpy tread. The speedo is almost spot on with these tyres as well. I had to cut the edge off my bullbar because the STT's would rub when hitting a bump and I couldn't go to access mode. No other probs with traction or stability control but they don't handle too well on the highway so I drive more slowly through corners.

Have fitted Mickey Thompson 265/70/17 ATZ 4 rib. Speedo is spot on with GPS but have knocked fuel consumption around horribly. The TDV6 uses heaps more to turn these tyres around. I'm just back from doing the Simpson and rubbing on the dips has ripped a few strips out of the inner guards. Otherwise no affect on road driveability.

My fuel consumption increased by more than 1L/100K when I put larger Coopers HT+ at 265/60/18 which increased tyre diameter by 9mm to 772mm.

Have a read of the car bible web site, they have lots of info on tyres which I found interesting. Car Bibles : The Wheel and Tyre Bible Page 1 of 2

Ryall

Originally Posted by lrdef110

Have fitted Mickey Thompson 265/70/17 ATZ 4 rib. Speedo is spot on with GPS but have knocked fuel consumption around horribly. The TDV6 uses heaps more to turn these tyres around. I'm just back from doing the Simpson and rubbing on the dips has ripped a few strips out of the inner guards. Otherwise no affect on road driveability.

I would agree totally about the fuel consumption, I think about 2lt per 100 difference at least. Interesting your findings on the speedo....mine is fine up to about 80kph (you don't notice the error anyway) and after that mine reads about 97kph when the GPS indicates 100. At 100kph on the speedo the GPS is reading 105 plus so I have to be very careful not to become a revenue raising film star

My front tyres also rub on the chassis rails on full lock so they are nicely polished.
Typical of an agressive tread you will also notice some more noise on the road though it is not excessive.Otherwise they are an excellent all round tyre doing well on wet tarmac, mud, rock and gravel and I would definitely put another set on.

Hi guys, first post....

I'm really suprised that such a small difference in size can have such a big impact on fuel consumption. Is it more to do with tread pattern?

I might be mistaken but according to the LR Australia brichure you can get 255/60 R18 tyres as standard or 255/55 R19 as standard.

Looking here Car Bibles : The Wheel and Tyre Bible Page 2 of 2 suggests that those two sizes have about a 30mm differnce in diameter and a 5% difference in circumfrence but are still fitted to the same car with presumambly the same gearbox & diff ratios?

Seems odd to me??

Munners17

Re fuel consumption fitting the bullbar to my D3 made more difference to fuel economy that going to the 18"General Grabber tyres (same size as wranglers ) so I'm not convinced it's the tread pattern.

Regards,
Totes

No Munners, the ATZ 4 rib is a pretty clean tread, certainly no worse than Grabber AT2's but the TDV6 certainly makes hard work of the greater diameter. In fact it often decides to hold 5th gear instead of uploading to 6th on the highway. Manual overide can help this but around town i'm up about 3 litres per 100km. Mine is chipped so there should be plenty of power to handle the extra tyre height, just likes a drink to do it.

G'day Munners,

To check tyre sizes and diameters I use Tyre Size Calculator @ ExplorOz where you can compare different sizes easily.

Re the 255/60 R18 and 255/55 R19 tyres, the 18's are 763.2mm and the 19's are 763.1mm in diameter which would be covered by normal variation in a set of tyres the same size.

Ryall