Transmission to Transfer Case Seal

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Alysium

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I cant find any info on this. Is there a seal between the 10spd and the transfer case?

If anyone has a diagram or a service manual for this, id appreciate it.

looks like I have a small leak between these two components.
 

FordTechOne

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There is no gasket between the transmission and transfer case. The transmission is sealed by the output shaft seal and the transfer case is sealed by the input shaft seal. You may want to add dye to the transfer case to see which component the fluid is leaking from.
 
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Alysium

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ok, thank you! I'm assuming a UV dye would suffice.

regardless, when I find which seal is leaking, is the seal replacement straightforward on the transmission output shaft?
 

FordTechOne

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ok, thank you! I'm assuming a UV dye would suffice.

regardless, when I find which seal is leaking, is the seal replacement straightforward on the transmission output shaft?
Yes, nothing unusual. They recommend a seal puller and slide hammer for removal and a seal driver for installation. They make UV dye that is specifically designed to be compatible with transmission fluid.
 
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Alysium

Alysium

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does anyone have a copy of the manual for replacing the transmission output seal? seen some info out there that I have to remove the downpipes to remove the transfer case??

finally had some time to install a PPE pan, new filter, fluid and UV dye. the leak is coming from the mating surface of the 10r80 and transfer case.

UV dye confirmed its transmission fluid and not transfer case fluid.

I think the output shaft seal part number is HL3Z-7052-B but not 100% sure on this.


10r80-10-speed-transmission.jpg
 

sc85fiero

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Keep in mind, the front and rear driveshaft need to be removed to remove the transfer case, there are several one-time-use bolts including the transfer case to transmission, insulator mount nuts, driveshaft bolts, etc. Exhaust shouldn't be in the way, you won't have to remove it.

-Joe
 
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Alysium

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Keep in mind, the front and rear driveshaft need to be removed to remove the transfer case, there are several one-time-use bolts including the transfer case to transmission, insulator mount nuts, driveshaft bolts, etc. Exhaust shouldn't be in the way, you won't have to remove it.

-Joe
Hi Joe, thank you for all your input.

I figured I didn't have to mess with the downpipes to remove the transfer case but I saw a few videos that required its removal to be able to drop the crossmember supporting the transmission mount.

Yeah, that's why I was wondering if anyone here has a copy of the service manual so I can make sure to replace all of those one time use bolts as well as review the shop procedure of replacing the seal.
 
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