In 2017 the Ford F250/F350 received a new Dana 60 SHORT Pinion High Pinion front end. This front requires a 4.56 and numerically higher carrier such as the ARBRD166. It will require a Short Pinion High Pinion type ring and pinion which is only made up to a 4.88 ratio. This new front end uses different pinion bearings and associated parts on the pinion than the earlier Dana 60 front end. The 2017 F250 can be equipped with a 12 bolt Sterling 10.5” rear end which can be regeared to a 4.88 ratio to match the front. Some of the heavier GVWR 2017 F250 trucks have the larger Dana M275 rear diff and the highest numerical ratio is 3.73.