New Rear diff cover and fluid change

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Raptorlander

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You need to torque those grade 8 bolts to a higher spec than the stockers or they will come loose.

Non-graded 5/16 bolt takes approx 5 ft-lbs to properly stretch. Grade 5 5/16 bolt takes approx 10 ft-lbs. Grade 8 5/16 bolt takes about 20 ft lbs to properly stretch the bolt and achieve a clamp load.

You also need to make sure the material the bolt is threaded into can take the higher torque rating when you start making changes. Probably not an issue here given the cast iron diff and realtively small change in torques- but it can be a major problem in engine blocks. You can't swap from stock head bolts to ARP 2000 bolts that take another 75 ft-lbs to achieve a clamp load in every engine block, as it can deform the block or rip the threads out entirely, depending on the engine.
Didn’t torque mine to any spec except to bottom out and tighten a bit more. I’ve wheeled hard since at merus adventute park (including one black diamond trail), Big bend National park trails, big bend ranch trails, and this past weekend Bridgeport off-road. No issues, no leaks at all. Upgrade to a lube locker gasket and all is still well.
 

R Level

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who out there has purchased/installed the Spicer Dana Rear Diff for a 2019 Gen2 Raptor? Is this the correct Model: 10023539
 

BalanBro

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who out there has purchased/installed the Spicer Dana Rear Diff for a 2019 Gen2 Raptor? Is this the correct Model: 10023539
While I have a Gen1, I'm 99.9% sure it fits yours as well. I checked Ford parts, the OEM cover is P/N: BL3Z-4033-C. This diff cover is listed as compatible for F150s from the 90s up to and including 2023 with the 9.75" axle.

While you're at it, pick up the lube locker gasket to make the install a breeze. I just did mine 2 weeks ago.
 

thatJeepguy

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Didn’t torque mine to any spec except to bottom out and tighten a bit more. I’ve wheeled hard since at merus adventute park (including one black diamond trail), Big bend National park trails, big bend ranch trails, and this past weekend Bridgeport off-road. No issues, no leaks at all. Upgrade to a lube locker gasket and all is still well.
Spec is 22-33 lbs very light
 

KingKoopa17

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who out there has purchased/installed the Spicer Dana Rear Diff for a 2019 Gen2 Raptor? Is this the correct Model: 10023539
Just bought mine from Rockauto last week (Amazon wouldn't deliver until early January), also with the Lube Locker gasket. That is the part number I punched in and, after a quick minute or two of research just to be sure, pretty certain it's the correct number.

Edit: For the record, I also own a '19 Gen2.
 
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