ObiHann wrote:
Wouldn't it be the same as say, having a car that runs a mini spare?
If you have the select trac t-case you can not use full time 4wd with a smaller/larger spare.If you have a auto locker(like a Detroit or any lunchbox locker) or a LSD you can not use a smaller/larger spare but only on that axle with the auto locker or LSD only,it's okay on the diff that is still open.
Vehicles with those donuts do not have a full time 4wd option,LSD's,or lockers offered.All vehicles with the before mentioned items(OEM) will come with a full sized spare or at least a same height spare.If you put these items on you need to get a same size spare or damage will result.
Basically don't be cheap and buy 5 wheels and tires of the same size,not 4 to save some money,more so if you drive a Jeep

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