Is GL-5 bad for our transmission

[TQuentin1]

GL-5 is essentially the pressure rating of the oil. The additives in the oil are what provide this protection. Apparently, some of those may lead to corrosion of the "yellow" metals that might be used in some transmissions. I am not sure of the material of all of the bits in the tranny, but suspect there may be some brass. It seems from their response, that Spectro is aware of this issue and has added something to mitigate this corrosion.

TQ

 

[porkchop]

GL-5 is essentially the pressure rating of the oil. The additives in the oil are what provide this protection. Apparently, some of those may lead to corrosion of the "yellow" metals that might be used in some transmissions. I am not sure of the material of all of the bits in the tranny, but suspect there may be some brass. It seems from their response, that Spectro is aware of this issue and has added something to mitigate this corrosion.

TQ

I am starting to second guess the idea of using a GL5 in my tranny now. It may seem good in there for now but in the long run it may do some harm in there. I have been using gear oil for about 15k so far and it seems to work good but later on maybe not so much. After all, Harley did stop using GL5 and went with the F+ witch is a GL1, There might be more to there reasoning for this than to simplify there lube line up.

 

[porkchop]

F+ is for the primary
HD stop using syn3 in transmission for good reason it was not getting the job done

I am not talking about the syn3, F+ is primary and tranny (per HD) They used to sell GL5 gear oil for tranny's but then stoped and come out with F+ for a reason.

 

[Jack Klarich]

F+ is for the primary
HD stop using syn3 in transmission for good reason it was not getting the job done

And The MOCO has told the service departments to get that junk out of the trannys and use gear oil imagine that they admit to a mistake :s

 

[jdeatsch]

GL-4 is getting harder and harder to find.

I managed to find some Quaker GL-4 for a buddy of mine's gearbox (Little British Car) but it weren't easy I tell ya.

Jim

 

[TQuentin1]

I am starting to second guess the idea of using a GL5 in my tranny now. It may seem good in there for now but in the long run it may do some harm in there. I have been using gear oil for about 15k so far and it seems to work good but later on maybe not so much. After all, Harley did stop using GL5 and went with the F+ witch is a GL1, There might be more to there reasoning for this than to simplify there lube line up.

Couple of things here. HD Formula + is not a FULL synthetic gear lube. I like it for the Primary as well as Spectro Primary. To me, both of these products are fit for purpose there in the Primary.

But I think that a gear lube with a higher pressure rating is important for the tranny. But if you are worried about things, call John Dunne at Spectro and discuss the issue with him. If you don't get a satisfying explanation of what they have done, switch to a GL-1 gear lube.

Since I change my fluids all at once when I change engine oil, I am not concerned. I work for an oilfield specialty chemical company, and I understand the need to add components to products to counter-act an unintended consequence of another component that is in the product to fight a major problem.

Here is Mr. Dunne's contact info:

John P. Dunne
Spectro Oils of America
Specialty Sales Manager/Private Label
Tel # 203 775-1291
Fax# 203 775-8720
Cell# 203 770-4546

TQ

 

[Jack Klarich]

I am starting to second guess the idea of using a GL5 in my tranny now. It may seem good in there for now but in the long run it may do some harm in there. I have been using gear oil for about 15k so far and it seems to work good but later on maybe not so much. After all, Harley did stop using GL5 and went with the F+ witch is a GL1, There might be more to there reasoning for this than to simplify there lube line up.

GL5 will be just fine as we have no brass synchros in our trannys, and the MOCO has told its service reps to stop using syn3 and formula plus in the tranny and go back to a gear lube. The formula plus equals about a 50 weight lube, HMMMMM sounds like oil to me:s

 

[oldhippie]

I was reading around about transmission oils and I came across this link

Does Gear Lube Corrode Yellow Metals

probably need to copy and paste but anyways can someone please enlighten me a little further, I see alot of people recommending Spectro 6speed transmission oil and lots of other GL-5 rated oils but the mobil 1 site says its not good to use GL-5 rated oil in harley transmissions due to the corrosion of "yellow metals" like brass and copper..... Is there copper and brass or any other yellow metal in the transmission? I was going to buy mobil 1 75w90 gear oil cuz i heard it was not best to run 20w50 in the tranny, so i am confused I know you can run 20w50 in the tranny but its not the best option. anyways Could someone straighten me out? Oh and if your only reply is look in the oil section or something to that nature please do me a favor and don't reply. Thanks.

I guess if Mobil 1 will not stand behind their gear oil being used in my tranny, I will not be using it in there.
I'll go with a product that is marketed and sold as being made for our big twins tranny. Be it Bel-Ray, Spectro or Red Line with HD Formula + as a last choice.

Guess I'll be dumping my QS syn out of it soon since I doubt they'd stand behind it being used either. Good thing I have a bottle of Bel-Ray 80W90 sitting waiting.

 

[NEWHD74FAN]

GL-5 is essentially the pressure rating of the oil. The additives in the oil are what provide this protection. Apparently, some of those may lead to corrosion of the "yellow" metals that might be used in some transmissions. I am not sure of the material of all of the bits in the tranny, but suspect there may be some brass. It seems from their response, that Spectro is aware of this issue and has added something to mitigate this corrosion.

TQ

Gear oil that was designed with the application in mind is what I would go with. Spectrol is good lubricant and quite honestly motor oil is probaby 80% additives these days, with all the mutli-grade additives, heat and corrosion fighters, wetting agents to make it stick more to parts, anti-wear ingredients...:small3d015:

Synthetic Oil just capitalized on the fact that crude can be refined into a fine product, but this "new" technology has long since dissected the best properties at the molecular level and thus improved upon the purity of oils. 100% Synthetic (man made) oil is a moniker, and a money maker to be sure...for the oil companies. Higher temperature tolerance and antiwear additives, and ingredients to "mitigate" possible problems is just a part of that porcess...

 

[dangerdan]

Here it is I went to SPECTOR and ask them about this
Our GL-5 fluids will not harm a Harley trans. .The soft metals you mention are in antique auto equipment, not what you have. John



John P. Dunne

Spectro Oils of America

Specialty Sales Manager/Private Label

Tel # 203 775-1291

Fax# 203 775-8720

Cell# 203 770-4546

Good research Smitty. Hope that resolves this issue for good