Jump to content

Sta Lube GL4 (NAPA) may be the GL4 pick (dino oil)

Recommended Posts

I need some GL4 for my 1974 620 and discovered this Sta Lube which is dino oil.


Lots of praise from all kinds of auto communities where the consensus is that dino is better than synth (although probably related to synth being thinner.)


But the real closer for me was a guy who raced Ford TopLoaders in 1965 (the biggest, baddest 4-spd of the muscle car era - so good, I put one in my 1963 factory supercharged Studebaker Lark which originally had a Borg-Warner T-10)


So I'm off to NAPA and going to buy a Big Bucket of the stuff.  Never know when it might disappear.  It appears the Sta Lube is more of an industrial line of oils, which means the spec will not be under pressure to change like it is in auto-land.


NOTE:  some comments on what I found on the shelf at Advance and Auto Zone:

  • Valvoline High Performance Gear Oil:  factory says GL4 and GL5 and will not corrode brass, however on the bottle says:  GL4/5 for differentials, and non-synchronized transmission that require GL5. 
  • Pennzoil Synchromesh:  Says GL3 and a specific replacement for a few factory P/N lubes.
  • Lucas:  GL4 and GL5 and a few others.  But no info on the bottle.  Their bottle art looks like it was done like a Comic Book.  Very unimpressive.
  • GL5 everything else.
Link to comment
  • Replies 19
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Gear oil has come a long way since '64. Synthetic is slipperier, thinner, lasts longer than the 'dyno' oil. I'm running GM Delco Synchromesh Transmission oil. Only down side is it can weep past an old rear seal. Faster shifting, better shifting when cold, slightly quieter and WAY better down shifting than the 90W GL-4 I had in it. 




Lordco about $17 CDN a liter. Would have bought it at the GM dealership but when I gave him the part number he wanted to know the vehicle VIN. I said it didn't matter I knew what I wanted. He began arguing that it did matter so I said '76 710 Datsun and he got butt hurt. He could order it in for me.... so I left.

  • Like 1
Link to comment

I tried to see that "Yellow Metal Safe" logo on packaging and didn't find it on anything at Advance or AutoZone.  (Of course, I might have missed it.)


There is a discussion how the GL5 deposits a sacrificial layer that when it is worn off, it peels a micron of brass  with it.  GL4 peels off w/o brass loss.  Rings in GL5 will look black while in GL4, nice shiny brass.


As far as wear, most of us will not get close to seeing a worn out synchronizer.  However, my interest is will the transmission shift easier.  (And I have that personal interest in what is best for the TopLoader.)


Here is a URL with pics and discussion of all this.  It is a serious racing site.


GL5 followed by GL4:



  • Like 1
Link to comment

GL-4 contains a sulphur containing anti scuff compound at 'about' 4%. The exact same compound is used in GL-5 but at 'about' 6%. This is not a 2% difference but a 50% difference! so never use GL-5 in a transmission with copper alloys. Transmissions don't need the extra scuff protection because the gears are cut differently and transmit power differently than a differential.

  • Like 1
Link to comment

Found this info on the 4014 fluid:


The GM friction modified synchromesh fluid (OE#12377916) is used in a select crop of New Venture units that have friction lined blocker rings that need the additive package present. I am aware of no other uses for this fluid besides the stock applications.


Here is the link


Sounds like these transmissions have the rings lined with material found in automatic transmission clutches.


Mopar was notorious for running ATF in their old 4-spds.  People have quoted FSM's that said ATF for cold climates, GL4 90w for warm.


There seems to be tradeoffs for Temperature, Wear, Load, and Synchronizing. 


What is irritating is that the manufacturers, including the oil companies, do not spell out what the intended use of the oil is.  And when it comes to synchros, it's even more nebulous. 


Synchros come in brass, friction material, carbon fiber, and scintered iron and each one of those needs particular oil properties.


Then things get real complicated in transaxles where you have synchros and limited slip clutches living in the same oil.  Perhaps manufacturers designed the same friction material for both tasks or at least no oil incompatible types.


I talked to a friend that just put ATF in his Mopar 4-spd and said it shifts like "butter."  It's a barely streetable drag car with a B1 and big HP.


But then I've seen a T56 (uses ATF I think) with the gears worn away so that the tooth tips were sharp (no thickness!)


I was hooked on the Sta Lube GL4 because of the TopLoader drag reference since I have experience with the transmission and let me tell you, it does not shift easy.  (The Mopar guys talk about their A833 4-spds almost bragging they are "beasts" and hard to shift, but you can pound the crap out of them and they do not break - a real "manly" transmission.  I don't know if I'd be so eager to brag about that.)

  • Like 1
Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.