Determine what gear oil to use if I have G80 code

1999 CHEVROLET TAHOE
200,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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GROVER333
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I only want to use AC/delco oil but not sure to get the SAE 80w-90 GL-5 (not synthetic) or the SAE 75w-90 GL-5 which is synthetic. Also, if I get the synthetic to I need additive too?
Feb 17, 2020 at 10:29 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
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Good afternoon,

I posted the specs for you for both differentials. The second one is for the front.

No, to the additive.

Roy
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Feb 17, 2020 at 11:14 AM
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GROVER333
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Thanks. This is helpful. I have the 1999 old body Tahoe... the years lead me to believe these specs are for newer model Tahoe. Can you please confirm?
Feb 17, 2020 at 11:36 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
The 1999 to 2001 is for your truck.

You are welcome.

Roy
Feb 17, 2020 at 11:40 AM
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