Changing Tyre Sizes

[pauljygrant]

Just some comment after changing tyre sizes on my Navara.
The original tyres were 255/65/17 and i changed to 265/65/17. Both are Goodyear Wrangler but changed from highway to all terrain tread pattern.
With the original tyres, the sat Nav gave a speed of 93/94 km/h when cruise was set 100. With the slightly larger tyres (with maximum tread), the sat Nav now reads 94/95 km/h so only slightly different change to speed.
New size was significantly cheaper, presumably being a more popular size. Happy to benefit from a 4 for 3 deal at Goodyear Autocentre. - $846 for all 4 tyres. Got 75,000km out of the last set and wear was even - will see how the different tread pattern goes.

 

[Jimbo]

Good to know. I'm considering the same on my Prado. Going from 265/65s to 275/65s.

 

[Mark13]

If you want to make the speedo more accurate you would have to go up in size not width... For example go to a 265/70... The 265 is the width of the tyre in millimetres and the 70 is a percentage of the width in height.... So that would be a 185.5 mm from rim to tread instead of 172.25mm from a 65 series tyre... Also if your speedo was about 5% out, increasing the size by 5% (going from 265/65 to 265/70) will mean an increase in speedo by 5%, so your 94/95 will become 99/100 so speedo will be accurate...