Transmission/transfer Case Fluid

I just got a '59 CJ5 and I've begun checking fluids throughout. Most haven't been change/serviced in decades so I'm refilling or changing as needed. I bought SAE 90 Gear oil per specs but when I was ready to drain I noticed that the transmission is dripping a red fluid. I've asked but no ones seems to know of a red gear oil so I'm inclined to believe the PO used atf instead. I asked him and he assured me its gear oil but I'm really not sure.

Do I need to flush the transmission / transfer case in any way before adding gear oil, or should I try to stick with the atf? I'm not sure what type was used before. Thanks!

 

Some synthetic gear oils are red (RedLine?). Unlikely it's ATF. Synthetics are not good for these transmissions.

There's lots of discussion of this topic in old posts. Consensus is you should use 85W90 GL-4. Stalube is the most common choice.
https://www.amazon.com/CRC-Sta-Lube...0M8RYMC/ref=pd_lpo_1?pd_rd_i=B000M8RYMC&psc=1

This is a popular topic. LOTS of discussion in old posts: site:earlycj5.com GL-4 - Bing

If it's clean and not full of water, I'd just drain it well and put in the GL-4. Even if it's ATF, that's just oil and a lot of detergents. Should be 100% miscible. Realize that the transmission and transfer case share oil slowly, so whatever you put in need to be in both.

First post! Welcome from Boston.

 

Thank You! Ill look at those older posts and get me some GL-4!

 

A tip buy a small garden sprayer remove the plastic wand replace it with 2ft of 1/4ID rubber hose and use that to put your gear oil in. Pump it up and while it will be slow its a lot better then those stupid little pumps. Label it for your GL-4 Also have a container to put the hose in when done as it will drip out until the hose past the valve is empty.

 

Egads man, that's brilliant..

 

FlyinCj5 welcome.

 

I learned a new word today!

 

contact Brian Hainer at metalshaper@comcast.net. He sells all the lubricants for our Jeeps.

 

My usual disclaimer - when you go to buy GL-4, don't believe the counter guys who tell you "This GL-5 is just the same..."

I buy it on Amazon.

 

And the Amazon price is pretty responsible. One of the few correct spec oil to be found these days.

 

I recently changed my trans and t-case oil with the Sta-Lube GL-4. Got it off Amazon.