Gear oil compatability

[hole]

I've been told by a couple of respected mechanics in my area not to mix GL1 gear oil with GL5 because it will turn into a tar like goo . That said, does the gov still use GL1 in the trans/ transfer case or do they use GL5 with the MT1 rating? Just to be safe I'm going to drain trans/ transfer and refill with GL5 as I dont like tempting fate ( or Murphy) GL5 is about $35 for 5 gal here so its not that big a deal, what does the well respected SS members think? TIA Will

 

[Recovry4x4]

I've mixed them before with no known issues. Dunno what the Gov't is using.

 

[hole]

Thanks Kenny, the guys out here , including a Shell Oil distributor ( only place I could get GL1) made it sound like it would lock the trans up right away so it had me concerned. Thanks again! Will

 

[SasquatchSanta]

It is my belief that GL-1 was the standard spec when the trucks were built and over the years GL-1 was replaced by GL-5. I "believe" that GL-5 can be used in place of GL-1 as long as it is also MT-1 (yellow metal compatible). I'm not sure of all this and I also do not know if it is harmful to blend GL-1 with GL-5.

Just today, my CarQuest delivery guy dropped off a 5 gal pail of GL-5 80W-90. I had specifically told CarQuest when I placed the order that it MUST be GL-5 AND MT-1. The pail doesn't say anything about MT-1 so I called CarGuest. I was told they called Valvoline and was told that even though the bucket didn't say anything about MT-1 that it was indeed is. I leary.

The 80W-90 I got says it doesn't contain zinc. Does anyone know if zinc has anything to do with the MT-1 factor.

"Hole" --- I don't mean to step on your thread buy maybe we'll both learn something with this.

 

[DanMartin]

GL4 is the "official" replacement for GL-1 (did not have as much of the high-pressure additives at GL-5, which caused the yellow-metal incompatibility). GL-5 with MT-1 rating is compatible with GL-4. I just purchased 5 gallon pails of "GL-4/GL-5 MT-1" 80/90wt from Costco. Basically multi-use gear lube. ($39 per bucket).

Basically if it's MT-1 you're good-to-go. The old GL-1 stuff was the solution in the 50's....time and technology have marched on and the yellow metal issues have been resolved. GL-5 is good for your tranny and your diffs (the GL-5 stuff works well in high-pressure applications like hypoid gears).

Soo...I'm changing out all of the lube in my deuce to this newer GL-4/GL-5 MT-1 stuff.

Hope that helps.

 

[SasquatchSanta]

Dan --- Sorry to be dense but are you saying that if it's GL-5 it's yellow metal compatable?

I'm concerned about five gallons of GL-5 that I just bought that doesn't say anything about it being MT1 (yellow metal compatible)

 

[DanMartin]

Must have the MT-1 rating to be yellow-metal compatible. I was trying to say that almost all of the new stuff will have this rating as it's pretty much all that is manufactured anymore.

There is a lot of old info out there that has persisted and become muddled with the new (as the starting message in this thread can attest to). A pretty low signal to noise ratio if you get my drift.

I've done some research on this (lots of web reading on this subject, including some official API documents that have been published)...but I am by no means an expert here. If someone would please check my work, I would love to hear any feedback.

 

[DanMartin]

...oh, and I did see a post about the Carquest GL-5. Current thinking is that it's made by Valvolene and packaged for CQ, and should have the MT-1 rating (as their offering does).

 

[racer-xerols]

Just an off-the-wall question here. What with changing lubes, draining old fluids and stuff...is it too simple to be able to put the stuff in the fuel tank with your diesel and just burn it off? Or will it cause filter/pump problems? (Yes, I'm a Multifuel newbie...)

 

[DanMartin]

I assume you're talking about the gear lubes...You'd need to filter it well (there will be microscopic metal shavings in there) and dilute it well, but it should work. The important thing is to thin this stuff out well...it's pretty thick stuff, and typically contaminated with all kinds of stuff (mud/water/grease/what have you). I would thin it before I filtered it to make sure to get all of the bad stuff out.

Personally I wouldn't run gear lube through my motor, but that's just me. Engine oil is fine if pre-filtered well and used in moderation.

 

[SasquatchSanta]

Thinks for the insight Dan,

The CarQuest guy that sold me the 80W-90 did indeed say it was made by Valvolene and confirmed that Valvolene said it was to MT-1 spec. The guy at CarQuest had never given me cause to doubt him but since it (the MT-1 spec) isn't written on the container I was a little concerned. It's kind of odd that the MT-1 spec isn't stated on the container.

Perhaps it because with the modern GL-5 lubricants MT-1 is more the norm than the exception.

Anyway, thanks for the insight.

 

[DanMartin]

I think it's important to note here that the only reason I would run the GL-5 (MT-1) stuff in my tranny is for convenience ...I don't want to buy different lubes (I'm lazy). There is no specific benefit of GL-5 running in a gearbox...it's made for differentials with high pressure gears (hypoid style). This is similar to why the Military ran GL-1 (type) in the diffs and gearboxes...one lube for the whole truck..less confusion. Early GL-5s had yellow-metal issues, so the military shied away from them and stuck with good old GL-1 (type) lubes...simple and easy to explain to the motor pool guys. However...the diffs weren't getting the best they could get...and I think this is (partially) why we see a lot of upper bearing wear/failure on the rockwells.

Now that the yellow metal issues seem to have been addressed, and it's "safe" to use the GL-5 (MT-1) stuff in the gearboxes, I will be using said lube in all the gearboxes and axles as it makes for a simple process (all out of the same pail).

Sooo...if you have GL-1 around, use it for your gearboxes (it's fine)...but go with the GL-5 stuff for the axles (they will thank you with years of dependable service). Don't have GL-1 (or Gl-4)?...GL-5 (MT-1) will work.

OK...I'll get down off my soap box now. Thank you everyone...goodnight....tip your waitress.

 

[hole]

Thanks Dan, thats more info than the Shell guys gave and then some. I did try to search the net on this subject but couldnt find any diffinative answers( but truth be told I sometimes struggle with modern gadgets )

 

[FSBruva]

Sasquatch..

Check the little bottles of the same type of GO at carquest. As I recall, the little bottles specify the MT-1, they just forgot about it on the big pail.

Matt

 

[Jake0147]

Re: RE: Gear oil compatability

I'm concerned about five gallons of GL-5 that I just bought that doesn't say anything about it being MT1 (yellow metal compatible)

Do be very concerned. It's a selling point, paint on the bucket is cheap, they could paint that endorsement on a LOT of buckets for the profit margin on that one bucket that you might or might not buy from them. There are many possibilities, but odds are they outsourced a "pre-fabricated" specification that was already certified. Valvoline brand oil might be blended by the same people that blended the Car Quest stuff, but that doesn't necessarily make it the same stuff.

...oh, and I did see a post about the Carquest GL-5. Current thinking is that it's made by Valvolene and packaged for CQ, and should have the MT-1 rating (as their offering does).

It certainly could meet the criteria, but like I said above, what's to gain by not stating so? Who is Valvoline? They're not quite the top of the food chain either, They're an Ashland brand. Ashland is primarily a chemical producer. If I choose to start selling my own brand of gear oil under a private label but produced (blended) and bottled by them, I can select from a very long list of pre-blended and pre-certified products, I can work with them and they can put together a product that meets my needs and may or may not be certifiable without further testing, or if I'm really sure of what I do or don't want I can just give them the spec's that I'd like and I can certify it myself, or maybe it won't even make any of the obsolete standards but is good for my purposes... Lots of choices, very different, but you could truthfully tag it all as "valvoline".

 

[Floridianson]

Little extra reading!

 

[Floridianson]

ok

 

[Floridianson]

last one

 

[sprucemt]

All the surplus oil from the US Military I have been recieving has been GL5-MT1, in the grades posted above.

 

[Floridianson]

Sorry had to edit: The Chevron rep said I must look at the list of ingreidents in the GL-4 GL-5 MT-1 gear lube that I would be useing as some still contain sulfur phosphorus. The Delo trans ESI lube uses inorganic borate and is safe for yellow metal but it is not cheap.
What brands are some useing as I would like to look into this more? James