New owner needs help with oil types

[1962m37]

Hi - just got a '62 M37 and after reading multiple forums and threads, I am confused to what I should be using for lubricants.

For the differentials, I believe I should use CRC Multi-Purpose Gear Oil 85W90? It is a GL4. The previous owner told me he was using a 85w90.
https://www.amazon.com/gp/product/B000M ... PxLgdZ-m-4

What about the transmission and transfer case? I've read so many different things. Is Lucas SYNTHETIC 50 WT TRANSMISSION OIL fine for both? https://lucasoil.com/products/heavy-dut ... azDcKlq3EM The previous owner told me he was using Synergyn 50W, but I can't find anything by that name.

Or should I run a cheaper GL1 in the transmission and transfer case? I see it at Tractor Supply as Ford Tractor Oil.

Since I don't know what's in there now, I intend to drain and replace. The rear diff and transfer case are low. The transmission is full, but has some brown to it. Front diff is full and looks new.

Thanks!

[NAM VET]

You will find various recommendations here, but be sure to use a non-sulfur oil in the transmission. For my transmission, I use a RedLine product for my transmission, a synthetic called MTL, makes for easy shifting, and no sulfur. For my transfer and axles, their 75-90 gear oil. Too thick an oil in the transfer case can hinder Lub and cooling. I have a magnetic drain plug in my engine, just to keep tabs of any suspicious wear particles.

One of the sudden dangers of these old trucks in the military fuel pump, which can have the internal pumping seals break down, and dump gas into the sump with abrupt thinning and damage. Read up on this. I use an electric fuel pump and have a block off plate where my oil pump used to be.

HC

[1962m37]

You will find various recommendations here, but be sure to use a non-sulfur oil in the transmission. For my transmission, I use a RedLine product for my transmission, a synthetic called MTL, makes for easy shifting, and no sulfur. For my transfer and axles, their 75-90 gear oil. Too thick an oil in the transfer case can hinder Lub and cooling. I have a magnetic drain plug in my engine, just to keep tabs of any suspicious wear particles.

One of the sudden dangers of these old trucks in the military fuel pump, which can have the internal pumping seals break down, and dump gas into the sump with abrupt thinning and damage. Read up on this. I use an electric fuel pump and have a block off plate where my oil pump used to be.

HC

Thank you HC. Will this 75-90 work in the transfer case and differentials? It's listed as a GL4 and GL5. Is there any yellow metal in the transfer case or differentials?

[NAM VET]

1962m37, couldn't get a PM to work to reply to you. The gear box has brass, not the diff's or transfer case. I get my RedLine products from Summit or Jegs, and use MTL in the transmission. The diff's are hypoid, so must use an oil with that in the spec for the oil, again 75-90 Redline for me. I use the same in the transfer case. I always tend to have problems with PM's but will try again in a few days with more. And welcome,,,, HC

[Cal_Gary]

(MOD POST) Guys, all pending posts have been approved for 1962... so PMs should now flow unhindered.
Thanks,
Gary