Per the owners manual:

SAE 75W-90 Axle Lubricant (GM Part No. 88863089, in Canada 88863090).

Anything that meets this spec should be fine.

 

I bet Amsiol hasn't updated there computer for this truck yet. It will probably be updated soon. I'll be using there severe gear in mine.

 

I emailed Amsoil and asked them about this. They told me they have not tested their gear oil against GM's new Dexron LS spec to see if their product meets the spec. In the mean time they won't recommend their oil until they are sure it's ok because they don't want to jeopardise anyones warranty. You guys can use what ever you want. All I have done here is pointed out that the part numbers in the owners manual point to the Dexron LS 75W90 Gear oil that meets GM's new production specification 9986285. Also if you don't use an oil that meets this spec and you have a problem you might not have any warranty. Again you can use what ever you want and take your chances. I can't and you can't know if there is something different about the diffs in these trucks that may not like the oils that are out there now. There are lots of really good gear oils on the market but they might harm something in the diff that we don't know about. If you can find another gear oil that specifically states it meets GM's spec 9986285 let us all know.

 

I'm curious if anyone has changed their Front &/or Rear Diff fluid yet?

If so did you use an alternative gear oil such as Amsoil or did you just go with the GM's 75W90 gear oil (Dexron LS gear oil production spec 99862865)?

 

I changed mine out to Amsoil severe gear not to long ago, Both diffs quiet as a mouse, seems even smoother at speed. I ordered new diff plugs which were about 8.00 as the plugs were already coated with thread sealant. Both bottom plugs are magnetic as well, both front and back are the same plugs....

 

I used the Amsoil.
AMSOIL Products for the 2015 CHEVROLET TRUCKS COLORADO (3.6L 6 -cyl Engine Code [3] LFX 4)

 

As someone noted, the 2016 Colorado owners manual only calls for "SAE 75W-90 Axle Lubricant". My 2011 Corvette Grand Sport owners manual specifically calls for "DEXRON® LS Gear Oil". I agree with the earlier assessment that the spec is SAE 75W-90 Axle Lubricant. Nothing more. We'll just say my front and rear diff were changed at 1000 miles.

 

I assume the Vette has a limited slip diff? Hence the requirement specifying "LS Gear Oil". I don't think the Eaton E80 requires that additive & I would guess any good quality SAE 75W-90 Axle Lubricant would be fine.

I'll probably go with Amsoil when I do mine.

 

Ok......

 

Yeah the Vette has a limited slip and they did have some major diff clutch pack chatter issues with the early models thus the later release of the GM spec Dexron LS fluid which I religiously use in it only as it is rather pricey... :wink2:

 

Both diffs have drain AND fill plugs. Drain plugs have magnets already attached and a sealant on the threads. Plugs are reusable.

 

And those diff plugs do a good job collecting break-in debris, here what mine looked like after a recent fluid change (Used Amsoil & have 20K on the truck). The last set of plugs are from the transfercase, they both come with no magnet but I epoxied a magnet to my drain plug as can be seen in the photo.

 

Amsoil Severe Gear FTW!?

 

CFans... Just to double check. I found no info in the owners manual or diesel supplement for the read differential gear oil. So what weight, 75w-90 or 75w-140 does it call for?

I'm zeroing in on 20,000 miles and want to replace it.

Thanks

 

Dealer tried to (he did) sell me synthetic gear oil for my G80.
I got suspicious about it and did some research.
My manual (2018) calls for GM Part No. 88863089, which is mineral based.
I don't know if I can use synthetic in my G80.
If the G80 seals are rated for synthetic, I can use syn and my fluid will have longer life.
If not, or if I don't know, I need to stay with the mineral.

 

Mobil 1 synthetic gear oil is compatible with all limited slip differentials and meets/exceeds the GL-5 requirement. It is pricey, compared to non-synthetic, but like all synthetics will flow better at lower temps which can aid in fuel mileage, though I don't know to what degree. But in Antarctica (or even the misspelled Antartica), low temperature flow characteristics should be important.

 

Looks lime Amsoil has got our 2nd generation trucks in their catalog now.

https://www.amsoil.com/lookup/auto-and-light-truck/2017/chevrolet-trucks/colorado/2-8l-4-cyl-engine-code-1-lwn-2-diesel-turbo/us-volume/

And 75W-90 is indeed the spec.

I had asked because Ford trucks must be some kind of an anomaly. My '99 F-150 and son's 2010 Ford Sportrac both were spec'ed for 75W-140.

I have two qts of Valvoline SynPower Full Synthetic 75W-90 LS (limited slip) ready to go in. That should work.