how to change rear pinion seal on 1990 f150
1990 Ford F-150: the pinion seal..rear differential..Two wheel drive. how to replace the pinion seal on the rear differential of a 1990 Ford F-150.ou need to rais ehte vehicle and remove the driveshaft. no turn the pinion by hand to see how it feels in rotational load. Now remove the pinion nut and pinion yoke. Replace the seal.