What GL rating should the transfer case gear oil have?

I have a VF2A transfer case. I know to use 75W-90 gear oil, but what GL rating should I use?

The Chilton says I can use GL4 or GL5 in the transfer case. Usually one GL rating is better than the other in a certain application, like the GL4 is better in a transmission because it has fewer additives that can react with bronze synchromesh.

 

Bump

 

After doing some research a few years ago, I ended up getting ALL kinds of conflicting information.

1. Just use the Toyota stuff, it's crazy expensive but you only need a quart. That is about $80 if I remember.
2. Use this instead, I did:

RAVENOL J1C1003 SAE 75W Gear Oil - MTF-3 Full Synthetic (1 Liter)

https://www.amazon.com/gp/product/B00QPCL7ZE?ie=UTF8 -- and that was about 30k miles ago? I am a big believer in change often so instead of buying really expensive stuff I just change the front/rear diff every 25k miles, and the transfer case about the same. No science here, so lots of people will blast me, but I use SuperTech walmart brand gear oil in the diffs and the Ravenol stuff for the transfer case.

(For transmission fluid, just pony up for the Toyota stuff).

 

If it's GL-4 in the transmission, then it's GL-5 in the differentials. I know it's one in the first, say transmission, and the other in the diffs. My problem is my brain is turning to mush lately, for whatever reason (whole different subject...), and I can never remember which is which. If you say GL4 in the transmission, I believe you. That means GL-5 in the diffs.

I know I went over this in a thread or three over on YotaTech. I'll see if I can find one of them. I know people who remember this stuff have corrected me a few times. Give me a little time...
Pat☺

 

You could always get a fluid that is compatible with both GL-4 and GL-5. I use this in the differentials: https://www.motul.com/us/en/products/gear-300-75w90

Haven't changed the transfer case fluid yet but Toyota confirmed it will work fine.