Why the switch to big rims?

[91RS]

Don't know myself, uninterested in owning a vehicle under 10 years old.
The operant question is:
Are the AT4s brakes so big, that they NEED 20" wheels just to clear the brakes?

Stock brakes, no. Brembos, yes.

 

[bryan8252]

Dont at4’s have 20’s?

Yes. The AT4s have 20" wheels with a 17" spare.

 

[olyelr]

Don't know myself, uninterested in owning a vehicle under 10 years old.
The operant question is:
Are the AT4s brakes so big, that they NEED 20" wheels just to clear the brakes?

If they have a 17” spare wheel/tire, my guess is no.

 

[Polo08816]

If they have a 17” spare wheel/tire, my guess is no.

I've seen this before. My guess is that if you had the Brembo front calipers and one of your front tires was not able to maintain air pressure, you would have to move a 20" wheel/tire to that position and put the spare 17" where you pulled the 20" wheel/tire from.

 

[Polo08816]

If you mean that you'll be spending an extra $2k-$3k to buy 17" wheels and tires,
some of that cost will eventually get defrayed by selling the 18" wheels.
The rest will be recouped over time buying cheaper tires.

Only people who think 18" wheels are NEEDED are those who sell wheels, tires, or vehicles -
and they're just trying to convince every one else that they 'need' 18" wheels.

18" (or larger / heavier) wheels are just more unsprung weight,
more wear & tear on suspension / steering bits, and more expensive tires, vs 17" wheels.

Don't know myself, uninterested in owning a vehicle under 10 years old.
The operant question is:
Are the AT4s brakes so big, that they NEED 20" wheels just to clear the brakes?

Anything over 20" is not necessary to clear any brake system that I know of.

However, if you want to maintain the 33" overall diameter for highway all season tires (ie. Michelin Defender LTX M/S2 and the Continental TerrainContact H/T), tires for 18" and 20" wheels provide you the most options. I don't see a need to move to 17" wheels. I definitely wouldn't want any wheel larger than 20".