You have a line going through the one and only radiator plus a small external cooler sandwiched between it and your ac condenser......which is the reason for having an extra fan.
My non big tow has that.I would expect a Tow Mode switch also.
You mean the size of the ring gear, because the pinion size will vary....3.36:1 uses a smaller pinion.*Lower gear ratio, the physical size of the gear doesn't change*
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