Separation in synthetic gear oil ?

Aug 8, 2006
Lafayette, La.
Trying to decide if I can use this 8 year old oil to top off in my Limited Slip (non G80) rear axle. It seems to disperse well once I shake it up. Any thoughts if this is Friction Modifier/Additive or maybe the grape scent GM puts in their oil?
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I can't stop laughing at how the bottle says, "New Grape Scent" :ROFLMAO:

To be honest I probably wouldn't use it. Never know if that's the EP additives, LS additives, etc. that have fallen out of suspension.
haha, yeah, I always thought that was odd gimmick for selling this oil ... all good points on the additives. Not sure if it makes a difference, but the truck is also 8 years old and yes, the bottle was half used, then stored.
The explanation I heard was because factory workers that had to fill the diffs on new vehicles complained of the smell so they added a scent to it to make it less unpleasant, I recently changed the gear oil on my 2008 Trailblazer and it was really filthy I wasn't sure if it was the factory fill or not, but I didn't smell anything other than regular gear oil, would the grape scent go away after 14 years and 175k miles?
Hmmm... in my experience all the good GL-5 gear oils smell like skunk.

I think those are the EP additives, the like sulfur/phosphorus. Always assumed that it it doesn't smell like that, the additives are gone.
the bottle still has the grape smell as does the axle when I pulled the plug to check the level. When I buy a new bottle, the OEM manual from 2004-2012 U.S. Colorado's calls for this (old # 89021677) new #10-4016/88900401, but it does not distinguish for LS or G80's. From all the research here and other truck forums, I am completely confused if I need to add some Friction Modifier/Additive (#1052358). Thoughts?

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How much is needed to top off, compared to the total diff capacity? If 10% or less, I would go ahead and use it. May sound arbitrary but this is my $0.02
I also wonder why a top off is needed.