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Transfer Case Leak - What Gasket?

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GMC-AT Senior Enthusiast

GMC-AT

Posted
Posted

2000 Silverado 4x4

NP 261 T Case

 

I have a leak from this gasket - the circle gasket at the very front of the TCase - that connects to the trans. What is the name of this gasket? 

 

My other question is does the case need to be taken all the way out to replace this seal?

 

 

 

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tbarn Senior Enthusiast

tbarn

Posted
Posted

4.515  GASKET, TRANSFER CASE ADAP (ACDelco #24245110)  (Service Lane Part) K1,2 1999 - 2000 01

There is the GM call out. May or may not be the correct number though. But that is the name in GM speak.

davester Senior Enthusiast

davester

Posted
Posted

Note, having the gasket there is kinda stupid, in that it makes it take longer to notice the real problem...namely, that either the transmission output shaft seal or transfer case input seal is leaking.

 

You could just replace the gasket, but it'll just leak again.  The area the gasket seals shouldn't have any fluid in it...

 

To fix it properly, you need to remove the transfer case, determine which seal (or maybe both) is leaking, replace the seal/s, slap a new gasket on there, then bolt it together.

 

I know gm has special tools for removing and installing the seals, as they aren't that easy to do with the shaft in the way...

GMC-AT Senior Enthusiast

GMC-AT

Posted
  • Author
Posted
Note, having the gasket there is kinda stupid, in that it makes it take longer to notice the real problem...namely, that either the transmission output shaft seal or transfer case input seal is leaking.
 
You could just replace the gasket, but it'll just leak again.  The area the gasket seals shouldn't have any fluid in it...
 
To fix it properly, you need to remove the transfer case, determine which seal (or maybe both) is leaking, replace the seal/s, slap a new gasket on there, then bolt it together.
 
I know gm has special tools for removing and installing the seals, as they aren't that easy to do with the shaft in the way...
Davester...thanks. I just had the back case half replaced due to a hole (pump rub issue)
I guess when they put it back together they screwed up some seals

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  • 3 weeks later...
dna9656 Enthusiast

dna9656

Posted
Posted
On 12/25/2017 at 5:44 AM, GMC-AT said:

Davester...thanks. I just had the back case half replaced due to a hole (pump rub issue)
I guess when they put it back together they screwed up some seals

Sent from my SM-G930V using Tapatalk
 

Did you get the pump rub problem fixed or did you just replace the case half? Merchant automotive.com has a very nice fix for the pump rub issue. I used it.

 

GMC-AT Senior Enthusiast

GMC-AT

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  • Author
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I already had a hole in my case, so I just replace the case half.

Sent from my SM-G930V using Tapatalk

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