Correct Transmission Fluid?

FWIW, I just ordered 2 gallons of the NAPA 65-201 GL-1 80w90 Gear Oil from a local NAPA store that will order it from the DC warehouse and have for me to tomorrow, so the GL-1 is available, but not likely to be stocked in too many stores, given the application.

My Jeep Service Manual specifies GL-4 SAE 90/80 (summer/winter) for CJ2-A.  Label states non-corrosive to non-ferrous metals - got it at NAPA.

Wow, i just picked up some Valvoline 80w-90 for my transmission/transfer case not thinking anything about the metals in there.  It's not the GL1 varient, I'm glad I didn't get around to filling them up yet!  haha  I think I'll hold out for one of those GL1 oils if I can find one.

  Could the oil companies be changing their ingredients in the gear lubes?  After reading all these replies I checked what I put in mine and it is G5 and it says on the label that it prevents corrosion of brass and bronze.  I believe I got it at Autozone.

   JIM

Many of the gear oils are now compatible to brass. I have checked some of them and it seems to be a hit or miss and you have to do some research for the brand you find or are using.  

Fred,

I have a similar manual, but it could be a year earlier.  It is titled a Service Manual and covers the years 1945-1964.  As Carl has mentioned, above, each lubricant has potentially different properties.  I, too, have seen GL-4/5 lubricants that say they are safe for yellow metals, and I have seen others that do not say peep about their ability to protect yellow metals.  I'm pretty sure your mileage will vary, and my object is not to prolong the discussion.  I do have one amusing anecdote that I will relate, below.

FWIW, my Jeep Service Manual that I referenced above, that I imagine is similar, though not identical to yours, specifies GL-4 lubricant for the CJ-2A transmission.  It also has one other amusing statement.  On the first page of the first section, General, it lists the Jeep vehicles covered in the manual.  It correctly describes the CJ-2A as having an L-head engine and the CJ-3B as having an F-head engine. However, this official Jeep publication also describes the CJ-3A has having an F-head engine!  "CJ-3A -- This is a 4-wheel-drive 'Jeep' Universal. It has a four-cylinder, F-head engine. This model is no longer in current production."  So, I'm not so confident that every statement in every official Jeep publication has been well vetted.  I wonder if your manual has been corrected in that respect or if the error persisted.  Mine appears on the first page of Section A, numbered page 3 in my case.


Edited by samcj2a - 26 Apr. 2012 at 4:35pm

Great read, I called our local NAPA and they never heard of GL1 , just a couple of kids, nice enough but really don,t know anything if it isn,t in the computer. Then I remembered driving past a place called oil mart on my way to work. Stopped in and told the guy behind the counter that I had a 47 Jeep and needed GL1 for the trans. He says just a minute, gets on a platform on a forklift and brings down a 5 gallon pail of GL1. Cost me $55 but now I,ve got enough oil for the trans-tcase for ever. So I mentioned I had read it was okay to use rotella in the motor because it still had zinc in it. He told me they had reduced the zinc level in rotella and to try Lucas zinc additive with good quality  oil. He advised adding 1 container of the additive with the first oil change then a half container  for the next changes. He said the Rotella being for diesels had to much detergents in it for an old motor anyway. Am I ever glad this forum exists, lots of great info.

Sam, somebody should be embarrassed about that - my manual says the same thing.  I thought inability to proofread was a characteristic of the 'New Century' but I guess not.  Hope they didn't make a mistake with the GL-4...

 

I just checked the fluids in my transfer case and transmission. Both are a mustard yellow color. I quickly check my oil bottles.....GL-5.... I feel sick. I have only put a few hundred miles on the jeep but the oil has been in there about a year.   Off to find some GL-1. I hope I have not done severe damage....