Transfer case fluid - a problem?

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9C1C

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I bought a 2004 Yukon 4x4 about 6 months ago. I'm changing the transfer case fluid today and got Valvoline synthetic transfer case fluid (says it's Auto Trak II compatible) since I have NP8 in my build sheet. I dropped the old fluid and it looks like not-too-dirty engine oil or gear oil. I expected it to be red since the new fluid is red. Should I be worried? Did the PO put the wrong fluid in there? My 4WD works fine, by the way.
 

Fless

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How much fluid came out? Any chance that the tranny seal is letting transmission fluid into the transfer case?
 
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9C1C

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Thanks - it looks like about a couple quarts came out, and none was red so I don't think I have a tranny leak into the transfer case.
 

rockola1971

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Sounds like someone filled the Tcase with Gear oil which is what the old steel Tcase you would find in a 80's Blazer took. Youd be suprised at how many people I run into that dont realize that the Tcase doesnt take gear oil anymore. Some people are still stuck in the old ways.
 

Rocket Man

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I can confirm that AC Delco AutoTrac II fluid is blue so it should look like what you described when it’s drained. Now that you're putting the Valvoline in…when somebody drains it and is expecting the AC Delco blue stuff….hope it’s you or there will be questions again. :gathering:
 
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