285/55R20 vs 285/65R18
285/65R18 is 0.8% taller (+0.24 in) and the same width than 285/55R20.
285/65R18 is 0.8% taller than 285/55R20. That is inside the ±3% most shops treat as a straight swap.
Real speed on 285/65R18.
Change in height under the axle.
On the same wheel, split inboard and outboard.
Shop 285/65R18 tires
Opens the store’s own searchPrices and stock change often, so check a few stores. We don’t earn anything from these links.
285/55R20 or 285/65R18?
Can I use 285/65R18 instead of 285/55R20?
285/65R18 is 0.8% taller than 285/55R20. That is inside the ±3% most shops treat as a straight swap. Also match or beat the original load index and speed rating, and check that the wheel width suits the new tire.
Will my speedometer be off?
At an indicated 60 mph on 285/65R18 you are really doing 60.5 mph if the speedometer was set up for 285/55R20. Going the other way, 285/55R20 would make it read 59.6 mph at a real 60.
How much ground clearance does it change?
Half the diameter difference: +0.12 in (+3 mm) under the axle.