Are there any differences between these oils besides the part number and shape of bottle?
Ac delco 75w85. 2 different bottles
- Thread starter 2013ecof150
- Start date
GM does this to us! Probably 2 different suppliers, who knows. They do these tricks with ATF Dex6 also. Will probably use a 75w-90 in my front and rear of the `16 Suburban. Maybe I'll use HPL diff life?
Still unclear about if I should use an oil with LS in the rear of the `16 Suburban.
Still unclear about if I should use an oil with LS in the rear of the `16 Suburban.
after closer inspection I just noticed the round one is a quart, the other is a liter …
Is your rear diff clutch or electronic locking or just non locking in any way which is what i personally prefer. If it's electronic or non locking use whatever 90 grade oil it doesn't need a limited slip additive or to be Full Synthetic. That is also 85 instead of the standard 90 so they're just trying to eek out FE to meet regulations. I'd just use a 90 grade from where ever even if it's conventional because the Full Synthetic stuff isn't worth double or triple the price which it shouldn't be but is. But you're better off changing twice as often.
I have 331k on my 05's original rear diff and all its ever gotten are infrequent 80w-90 changes about every 100k and it's fine to this day. Dead silent. Though gm made better quality trucks back then so I think I'll change more frequently on my 2021. I don't believe in changing rear diff oil super often if you don't tow. The temps stay low. If you tow a lot then the oil gets roasted. On a rear diff that isn't towing the temps on the highway while cruising are typically around 130f believe it or not. But towing and they go up to over 200f.
I had a friend that finally replaced the rear diff on his 01 silverado at 382k since he never once changed the fluid since new because a mechanic told him it lasts a life time and that it's pointless, and he believed him and trucked on. I asked him if it made noise and if it did when did it begin and he said the diff was silent until around 360k but he just kept driving it anyway. Never cared to change the oil and it still lasted a ton.
I have 331k on my 05's original rear diff and all its ever gotten are infrequent 80w-90 changes about every 100k and it's fine to this day. Dead silent. Though gm made better quality trucks back then so I think I'll change more frequently on my 2021. I don't believe in changing rear diff oil super often if you don't tow. The temps stay low. If you tow a lot then the oil gets roasted. On a rear diff that isn't towing the temps on the highway while cruising are typically around 130f believe it or not. But towing and they go up to over 200f.
I had a friend that finally replaced the rear diff on his 01 silverado at 382k since he never once changed the fluid since new because a mechanic told him it lasts a life time and that it's pointless, and he believed him and trucked on. I asked him if it made noise and if it did when did it begin and he said the diff was silent until around 360k but he just kept driving it anyway. Never cared to change the oil and it still lasted a ton.
It’s not for me at all. It’s for an 19 Silverado who belongs to a friend. He sent me those 2 pics from
Amazon asking if there was any difference between the 2 bottles.
I couldn’t find any specs on the fluid at all.
The round bottle is high efficiency 
Ask your friend the more important question which is if he knows if his rear diff is electronic locking or not locking at all or if it's a limited slip diff. If it's a clutch engagement limited slip diff then it just needs really whatever gear oil with a limited slip additive and if it isn't then the $5 bottle of gear oil at Walmart is all that it needs. If it needs the LS additive then spend a few bucks more for it.
But to be frank I don't know a single person who actually goes out of their way to get the specific x OEM gear oil. Especially for a domestic. Maybe for an import but just because it's an import. But they'll just use whatever they can find that is either limited slip compatible or not of it doesn't need to be and they'll put it in and they'll go hundreds of thousands of miles and have zero issue.
it’s a g80 rear so no Posi additive needed. He goes by the book, nothing wrong with that. I told him I’d buy the round bottle because it’s 5 dollars cheaper per quart or just go to the dealer with the last 8 of the vin number and use the gear oil they sell him.
Is that the stuff that smells like grape juice?
