# gmc 366 big block question



## chev_4x4 (Dec 28, 2006)

Have a 1990 gmc topkick with a 366 big block. Want to change the oil but don't know the oil capacity of it. Looked online several times could not find it. Coming here for all the answers I can't find anywhere else.


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## dieselss (Jan 3, 2008)

20 quarts if I remember. Or there abouts


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## dieselss (Jan 3, 2008)

I'm thinking I'm wrong. I can see the sharpie number, but I'm thinking that's the cat motor trk. Try 10 first


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## 2006Sierra1500 (Dec 28, 2011)

Start with 8 quarts, see where it is on the stick, add as needed.


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## maxwellp (Feb 16, 2013)

It should have an 8 qt pan. But? Try 6 and see if is on the stick and go from there.


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## chev_4x4 (Dec 28, 2006)

Thank you very much


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## peteo1 (Jul 4, 2011)

Why not call a GM dealer instead of listening to a bunch of guys on the Internet who aren't all that sure. Just because I'm a good sport I'll play too...start with 7 quarts and go from there


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## leolkfrm (Mar 11, 2010)

are you using a 1 quart or 2 quart filter? they came with both....should be 7 to 8 quarts


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