255/65 /18 as standard for 2005 MY...you'd prolly be ok with 15mm extra width either side but the rolling radius changes a wee bit, is it enough to be a problem I know not.
Comparing 255/65R18 against 285/65R18 WidthProfileRim DiameterDiameter
Tyre 1 255 65 18 788.7mm
Tyre 2 285 65 18 827.7mm
FITMENT NOT RECOMMENDED!
The percentage change is 4.71% and the circumference change is 39mm.
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