The 2 axles at the wheels have seals, the pinion shaft at the driveshaft also has a seal.The rear cover can be sealed with a RTV sealant (automotive type silicone )or a gasket, either one is fine.
Speed Sensor The sensor is located on the rear axle housing.
I believe you can find the axle code on one of the stickers on the end of the drivers door - then the code is used to find out what differential gearing your F150 has
how do you replace a Ford F150 rear axle seal
its located at the rear drive axle
110nm
For a 2001 F150, you can check the axle codes on your door sticker. The axle code to rear axle ratio values are as follows: 17 for 3.31 open differential, 19 for 3.55 open differential, H6 for 3.73 limited slip, H7 for 3.31 limited slip, and H9 for 3.55 limited slip.
Open the drivers door and look for an information sticker on the end of the door It will have the axle code for your truck
Disassembly
I believe axle code " 18 " is a 3.08 conventional axle ( non limited slip )
Mine is 3:55
My 2001 durango slt plus 4x4 has 9.25 rear axle and 8.25 front
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