Oil leak from front differential on K10

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InVision

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New owner here of a 1985 K10. I have a front differential leak near companion flange. It appears like I would basically remove the flange and replace the pinion oil seal. A few basic questions:

1) Can you get the seal? Wondered how to get part numbers.
2) Should I replace the gasket also?
3) Can this be done externally without rebuilding the differential? The front axle does not leak from anywhere else and runs exceptional well with little noise.

Thank you for any insight.

M
 

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RThiel

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Go to the parts store and ask for a pinion seal for the front diff on a '85 chevy K10. They should be able to look it up by application. You can change it without major disassembly. Rattle the nut off with an impact, tap the flange off with a hammer, remove the seal with a hook style seal puller, tap new seal on using seal driver, big socket, or by working slowly around the perimeter, reinstall flange, put nut back on and give it a quick buzz with the impact.
 

InVision

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Well that the best news I had on the old '85. So I should not worry about the outter Oil Slinger or gasket?

Thank you Sir so much for the help!!

M
 

VAL

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It's a good idea to count how many rotations the flange nut takes, to completely come off. When you reinstall, give it the same amount of rotations, so it's right back where it was. There's a crush sleeve in there that requires a certain amount of torque.
 

74 Shortbed

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Before you take the nut off put two dots with a center punch across from each other, when you put it back on tighten the nut up to the dots, then go just a hair past about half the dots width.
 

crazy4offroad

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Definitely dont want to over-torque it, since it only needs about 24 inch-pounds of rotational torque once pinion bearing preload is set. You also want to use red threadlocker on the pinion threads or it will back off.
 

InVision

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Got seal out. Thanks for the help !!

BUT, I was astonished to find no gasket (#5 in diagram) or (#6 in diagram) oil slinger. I removed the bearing and the race was fine. Bearing seemed to have some play so I will probably replace since I got it apart. Any ideas why no gasket or oil slinging.

Thank you

M
 

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