Gm GL-4 Ouch!

Cajun · Post by **Cajun** » Mon Jun 18, 2007 10:18 am

I just got back from the Chevy dealer the purchase the magic GL-4 SAE 80w-90 gear oil for my G-80 rear differential. $14.99 per 23 oz. container, where they came up with 23 oz. per container is a bit of a puzzle. Do we really need to use the GM brand lube as indicated in other post on this site? or does some other oil company refine an equivalent? Mobil 1 full synthetic?

killian96ss · Post by **killian96ss** » Mon Jun 18, 2007 11:04 am

Cajun wrote: Do we really need to use the GM brand lube as indicated in other post on this site?

No!

does some other oil company refine an equivalent? Mobil 1 full synthetic?

The Mobil 1 gear oil will work just fine and there are also a lot of other brands that will work good like Redline, Royal Purple, Amsoil, etc.

I use Redline 75W/90NS in all my 4x4 differentials and even on my SS.

There is nothing special about the GM oil.

The other brand names I listed above make really good synthetic gear oils that are better than the GM oil.

All you need to look for is an SAE GL-4, GL-5 certified gear oil in either 75W/90 or 80W/90.

Do not use any sort of limited slip additive or gear oil that is made specifically for limited slip differential.

Steve

Cajun · Post by **Cajun** » Mon Jun 18, 2007 11:55 am

Thanks Steve. I can always count on you!

Post by **HenryJ** » Mon Jun 18, 2007 2:05 pm

I will be sticking with the GM gear lube. Call me superstitious if you wish.

With RPO G80 1052271 only

Without RPO G80 (open diff) 1052271 or SAE 80W-90 GL5

GM Vehicle care Axle Lubricant SAE 80W-90
*excellent axle durability

1#1052271
Gr.8.800
23 fl.oz.

"Gm axle lubricant exceeds API GL-4 requirements and has been formulated specifically for use in certian GM axles as specified. Not all products labeled GL-4 will provide satisfactory service.

*excellent axle durability
*Compatible with limited slip fiction modifiers
*Compatable with seals/elastomers"

Contains : Petroleum oil (gear oil) - CAS 64742-65-0

HenryJ wrote:I opt for the recommended lubricant to supply the correct amount of friction required to operate the Eaton G80 differential.

Getting a chattering in turns from the rear end.
I don't recall the new part number. I am sure I paid close to $10 per bottle. Still pricey, but my preference as well as GM's recommendation.

killian96ss · Post by **killian96ss** » Mon Jun 18, 2007 4:22 pm

HenryJ wrote:I will be sticking with the GM gear lube. Call me superstitious if you wish. my preference as well as GM's recommendation.

I know we disagree here, but I would still like to point out a few things.

I have been using Redline synthetic gear oil rather than GM gear oil in my 88 S10 Blazer, 2005 ZR2 Blazer, and my old S10 CC which all have the G80 and all of them operate just as they should.

Of course GM wants you to use their fluid, they make even more money by doing this.

It's just a marketing strategy!

Have you ever noticed that GM recommends that you only use GM replacement fluids for everything that is serviceable?

It is just ridiculous to think that GM fluids are the best available and it is the only stuff that will work properly on your GM vehicle.

Redline, Royal Purple, Amsoil, and Mobil 1, make far superior oil products than GM offers not to mention they will protect better, increase performance and gas mileage.

I do believe in using genuine GM replacement parts for a lot of things like transmission filters, fuel filters, 02 sensors, spark plugs, etc., so in that respect GM does make certain things better than most.

I guess all that I'm really trying to say here is that as far as most stock replacement parts go, always try to use the GM stuff, but when it comes to fluids or performance upgrades there are just so many better choices out there.

Steve

F9K9 · Post by **F9K9** » Mon Jun 18, 2007 5:14 pm

How about you two agree to disagree and leave it at that?

Post by **HenryJ** » Mon Jun 18, 2007 6:02 pm

killian96ss wrote:...Redline, Royal Purple, Amsoil, and Mobil 1, make far superior oil products than GM offers not to mention they will protect better, increase performance and gas mileage.

Are you running them in your transmission?

killian96ss · Post by **killian96ss** » Mon Jun 18, 2007 6:31 pm

HenryJ wrote:
killian96ss wrote:...Redline, Royal Purple, Amsoil, and Mobil 1, make far superior oil products than GM offers not to mention they will protect better, increase performance and gas mileage.
Are you running them in your transmission?

No, synthetics are not good in automatic transmissions, however I don't use GM brand tranny fluid either.

Steve

WVHogRider · Post by **WVHogRider** » Tue Jun 19, 2007 2:03 am

killian96ss wrote:
HenryJ wrote:I will be sticking with the GM gear lube. Call me superstitious if you wish. my preference as well as GM's recommendation.
Of course GM wants you to use their fluid, they make even more money by doing this.

It's just a marketing strategy!

Have you ever noticed that GM recommends that you only use GM replacement fluids for everything that is serviceable?

Steve

Exactly.

For years, Harley-Davidson has always said to NOT switch your motor over to Synthetic oils because it will destroy your seals and gaskets.

They also sold & recommended their own oil as the only one to be used. Guess what Harley no longer offers in their shops----Dino Oil.

They have now switched over to only offering Synthetics. However, they still recommend their brand of Syn, but several mechanics from HD have said to go with anything that meets or exceeds the recommend viscosity/thermal breakdown/etc.

Post by **HenryJ** » Tue Jun 19, 2007 2:29 am

killian96ss wrote:
HenryJ wrote:
killian96ss wrote:...Redline, Royal Purple, Amsoil, and Mobil 1, make far superior oil products than GM offers not to mention they will protect better, increase performance and gas mileage.
Are you running them in your transmission?
No, synthetics are not good in automatic transmissions, however I don't use GM brand tranny fluid either.

Steve

The locking rear differential is the only one listed that does not offer an "or equivalent" statement.
All the others list a GM part number and specifications for a suitable lubricant.

Your reasons for not running synthetic in the transmission are the same I have for not running it in the Eaton GovLoc differential. I worry about the clutches having the friction that they need.
I know that Amsoil wreaks havoc. I have a guy that works with me that tried it in his fullsize.

killian96ss · Post by **killian96ss** » Tue Jun 19, 2007 6:45 am

HenryJ wrote:I worry about the clutches having the friction that they need.
I know that Amsoil wreaks havoc. I have a guy that works with me that tried it in his fullsize.

Amsoil does make good products, but to be honest I have never used their gear oil or motor oil so maybe they don't have the right ingredients for compatibility with clutches.

I am 100% positive though that Redline gear oil and Mobil 1 gear oil work just fine with the Eaton Gov-Loc.

Steve

Cajun · Post by **Cajun** » Tue Jun 19, 2007 8:44 am

I didn't mean to start a riot...I really appreciate everyone's help!

Best I can tell, neither GM or Eaton refine oil however I guess that they can specify how oil is to be refined but I fail to believe that even the mighty GM and Eaton can command a refiner's full capacity or even a line to produce the magic GL-4 Diff. fluid. basically their buying it from someone. I quess you could make the same argument against Redline.

For what it's worth...I spoke to the folks at Redline to get their recommendation for an equivalent to GM 1052271. They recommended their 75W-90 not the 75W-90NS. I spoke the the tech at length regarding the difference in their two products and reinforced the idea thethat our owners manual clearly states "No Friction Modifier". The Redline tech stated their recommended equal was the 75W-90 which contains some friction modifiers.

Does anyone know and understand the differences between GL4, GL5 and so on. Is GL5 a higher standard than GL4? or am I over simplifying things?

I am carrying around in my truck right now four quarts of Mobil 1, four quarts of Redline 75W-90 and the magic GM GL-4. I guess I'll toss a coin.
Right now the Mobil 1 sounds pretty good!

Your thoughts?

killian96ss · Post by **killian96ss** » Tue Jun 19, 2007 10:09 am

Cajun wrote:I didn't mean to start a riot...

Don't worry about it, we like to have discussions.

They (Redline) recommended their 75W-90 not the 75W-90NS.

NS stands for (no limited slip modifiers added).

I'm sure either one will work, however I chose the NS because I wanted to make sure that the Gov-Loc clutches would not slip, and I also have a few bottles of Redline limited slip additive so if I ever noticed any chattering I could add a small amount to stop it, but so far I haven't needed to do this in any of the 3 Gov-Loc equipped vehicles that I have.

Does anyone know and understand the differences between GL4, GL5 and so on. Is GL5 a higher standard than GL4? or am I over simplifying things?

I'm not really sure, but I thought GL-5 was for synthetic while GL-4 was for regular, but I could also be completely wrong.

I am carrying around in my truck right now four quarts of Mobil 1, four quarts of Redline 75W-90 and the magic GM GL-4.

I would still go with the Redline, but the Mobil 1 synthetic is also good.

Steve

Post by **HenryJ** » Tue Jun 19, 2007 12:42 pm

killian96ss wrote:
Cajun wrote:I didn't mean to start a riot...
Don't worry about it, we like to have discussions.

You bet! Ultimately you have to make the decision. Having all the information is what it is all about

a2b · Post by **a2b** » Tue Jun 19, 2007 10:05 pm

i buy gear oil all the time as i tear into my axles about 6 times a year. if i bought synthetic, i would be broke. i buy the cheapest thing i can get my hands on...if i can i buy the 80/14 stuff just cuz i like to pump for hours to get it into my tcase and tranny and diffs hahahahaha

Cajun · Post by **Cajun** » Thu Jun 21, 2007 6:05 am

For what is worth...out of pure curiosity I called tech support at the Torque Controls division of Eaton to get their take on alternate gear oil for their G-80 Differential.

Brule will be happy to know that Eaton says that OEM gear oil is best. I'm sure that goes for all fluids. The GM gear oil is synthetic. Interesting thing is that the engineer that I spoke to did not like synthetic oils at all. His alternative to GM's GL4 was any mineral based GL5 80W-90 gear oil w/o friction modifier. I also had the engineer confirmed that the GM GL4 gear oil does not have friction modifiers included. I thought that it was possible that the "NO FRICTION MODIFIERS" note in the owner's manual was there because the GM fluid included it as does Redline's recommended equal product.

I like choices and really take offense to anyone limiting my choice to their proprietary product. As I mentioned before, the Redline tech that I spoke with recommends their GL6/GL6 75W-90 as an equal to the GM gear oil. On the other hand I want to do whats best.

If anyone else is interested in talking to the Eaton engineer his contact number is 800-328-3850 ext. 6234.

Confused or maybe just hard headed.

killian96ss · Post by **killian96ss** » Thu Jun 21, 2007 6:34 am

Eaton recommends a gear oil with no friction modifiers which is why I use Redline 75W/90NS.

It is strange that the Eaton tech told you he does not like synthetic gear oil, but says that the GM GL-4 gear oil is synthetic.

I wonder why the bottle does not say that the gear oil is synthetic unless they switched formulas at some point in the past 4 years.

I am not surprised that Eaton told you to use the GM gear oil.

Don't forget that Eaton has a partnership and contract with GM so they are not going to go against GM's recommendation for gear oil.

If they did GM could lose money and Eaton could lose the contract.

Once again it's all part of a marketing strategy and has nothing to do with what actually works correctly in the G80 Gov-Loc.

I am 100% positive that other gear oils do work and in most cases work and protect better, however if you still feel unsure about what to use then you are probably better off just using the GM oil.

Steve

Cajun · Post by **Cajun** » Thu Jun 21, 2007 6:39 am

No doubt that Eaton and GM sleep together.

I think that I'll exchange my Redline for the Redline NS.

killian96ss · Post by **killian96ss** » Thu Jun 21, 2007 6:51 am

If you use the Redline 75W/90NS I think you will see that it does work perfectly fine in the G80 Gov-Loc.

I have over 140k miles of use in 3 Gov-Loc equipped vehicles using Redline 75W90NS, and have nothing but good to say about their oil.

Steve

Cajun · Post by **Cajun** » Thu Jun 28, 2007 9:50 am

I'm all lubed up front and back with Redline 75W-90NS and changed the transfer case fluid, Dexron III, while I had it up on the jack stands.

Thanks for everyones help!

T Man · Post by **T Man** » Thu Jun 28, 2007 4:21 pm

any synthetic gear oil will work. doesnt require additives like dyno stuff. On any of em

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