Ac Delco diff fluid need additive? Manual ss

[Matt8892]

I went to my chevy dealer and bought a bottle of their ac Delco differential fluid.

http://www.amazon.com/Genuine-889004.../dp/B00BK7LXGM

That one to be exact. I asked the gentleman in parts if I needed any additives and he assured me I did not because it's already in this and that's why it was so expensive. Is there any truth to that statement?

I had the fluid changed yesterday and drove the car for the first time this morning and I feel like I'm hearing a very faint metallicy sound coming from the rear when I accelerate on the harder side. But it seems quiet on turns.

Looking at that Amazon link however, you can see that the limited slip fluid is often bought together with the diff fluid....so now I'm worried. I just got the car with 10,000 miles on it And my mechanic did say the fluid was nasty.

Shoukd I get the additive and have that added asap? Can I just have it added if I need it. Any suggestions. Should I stop driving the car?

[el ess A]

What you have is the right lube for an SS, but GM says to add the limited slip additive for SS cars.

For ZL1 cars, the recommended lube has the properties needed that don't require the additive.

For fun, note that it says "new grape scent" and then below it warns you not to breathe the vapors. Idiots.

From the 2013 Owner's Manual...

[Matt8892]

Am I harming the car if I drive it another 20 miles?

[el ess A]

Very likely no. But the additive is more for clutch disc chatter on turns than going in a straight line. So if you're having metallic noises in a straight line, it may be something else and has nothing to do with the additive.

[Matt8892]

Well regardless, I'm at chevy now and they're adding the additive for me. See if that does anything and where I'm at with it.

[cajun1le]

Originally Posted by el ess A

For fun, note that it says "new grape scent" and then below it warns you not to breathe the vapors. Idiots.

Yeah, I laughed quietly inside when I read that as well....

Being that were on the topic axle lubrication, here's the analysis from when I had the fluids tested. I tested AC Delco gear oil, friction modifier and sampled the rear differential prior to changing. As you can see the friction modifier only only slightly thins out the gear oil viscosity without adding any additional elements to the mix (ie, boron). Also, it seems that Floyd vouches for the slight grape smell as well. lol Last time I had the engine oil tested he cracked a joke on Castrol Edge about how the advertisements boast the titanium additive and the sample came back with .2 PPM (parts per million). lol

[Andy-AMSOIL]

Ew stay away from ac delco... at least give your car something like red line