GL4 GL5 and confusing nomenclature

[blackstack]

It seems there are many names for the same thing and I am confused....using the names used in the little maintenace manual, is the following a true statement.

GL4 is used in the "change speed gearbox" and the "reduction gearbox" (see page 108 of the book) GL5 used everywhere else.

It makes my head swim when I read the posts and try to understand exactly which assembly is being referenced.

[pinzinator]

That is reference to the transmission and transfer case.

[blackstack]

Thanks.

I guess I wasn't clear in my question.

My question is : Is GL4 is to be used in both those locations ?

Some posts suggest that GL4 is for the "change speed gearbox"(transmission) only.

[krick3tt]

I use GL4 for all the boxes as I was instructed by several people that GL5 has ingredients that might harm some things (brass) and I don't want to be confused by two types of oil.

This is also a holdover from my Mog days when GL4 was the thing to use.
I had no manual for the Mog and it was a long time refurbishing it before I got the books.

I know, this is not a Mog!!! But it still uses GL4.

[blackstack]

This is from a post by Jim LaGuardia

Posted: Tue Mar 10, 2009 1:55 pm Post subject:

--------------------------------------------------------------------------------

First, everything uses 90wt GL5 gear oil except the transmission, it uses 90wt GL4 gear oil(2qts


My confusion continues

[krick3tt]

I would never dispute a Guru. Jim and the Prof fall into the category.

But...now that I have (and have had) GL4 in my boxes...will it hurt anything? Anyone feel free to interject an opinion.

I have even purchased the hex head plugs to replace the allen head plugs I have now, so that the next time I change out fluids I will also change drain plugs...Except the one on the very bottom, it is recessed for a reason.

Morris

[Jim LaGuardia]

You can use the GL-4 in all the boxes if you wish. Just a side note, Ex-2 Diff gearsets use bronze not brass bushings, so GL4 or GL5 is ok .
Now go have some fun

[blackstack]

Does the transfer case (reduction gearbox) in a 1972 710 have the brass bushings that would/might be damaged by using standard GL 5 gear oil?

[lindenengineering]

OOh
I can answer that!
The t/case CAME (past tense) with bronze synchros for Hi/Lo selection.
Apart from a few misc pieces the guts of the case it is all steel components.
Somewhere in the 70's/80's came sintered iron synchro rings that are much more durable than bronze and are not subjected to the "POSSIBLE" (and I express possible) corrosive effects of GL5.
Nowadays it's hard to know what might be in your t/case!

Now oil blenders are aware that GL5 "CAN" have an effect on yellow metals so they have changed the blend additives in GL5 to reduce the potential corrosive effects.
Checking with a potential oil supplier's customer hotline will confirm this.
When the Pinz came out there was only GL2 and it is very hard to locate GL4. Napa for example does an oil that is GL2 to GL5
compliant.

Of course you could always bung in synthetic oil at about 8 to 12 "clams" a qrt/litre and forget the whole blessed problem.
If you consult a big truck shop like MHC Kenworth and ask for gearbox/axle synthetic 90wt oil say for a Eaton RoadRanger 13 speed transmission, you can buy a 5 gallon pail of it for about 4 to 6 "clams a qrt.

Amsoil anyone?
Oh blue or yellow flavour?

Dennis
Ooh I will have smart assed flavour! "cos blue is cheaper" No kidding

[acebee]

trying to keep it simple...i use from the following choices.

TRANSFERS/DIFFS
- Sta-Lube SL24239 85w90
- Coastal 80W90 ( Jim L 's suggestion to me)

PORTAL HUBS
- Swepco 212 80-140
- Red Line Heavy Shockproof Gear Oil 75W250
- Chevron Delo® Gear Lubricants ESI 85W-140

BRAKE/HYDRAULIC
- DOT3

ENGINE
- Chevron Conventional 30W (winter)
- Castrol GTX 10W40 (summer)

Now the question..

Guru(s) ? am i doing something wrong ? :?: