GL4 transmission oil

Ok, I have a 46 Chevy 1/2 ton pickup 4 sp tranny.
I’m changing the transmission oil and have been told to use Gl4 80w90 oil that doesn’t contain sulfur and phosphorus, and not Gl5 because it will damage bronze and copper. The problem is I can’t find GL4 anywhere, tried all the parts stores. What I do find is some that are for GL4 and GL5 applications. My concern is does this contain sulfur and phosphorus? It doesn’t list ingredients on the bottle. Anybody know if this will be safe for my 46 transmission?

 

I bought my last bottle of GL-4 at Walmart about a year ago.

 

Hi Bill, unfortunately they no longer carry it. I did find StaLube GL4 on Amazon for $18 a quart.

 

This
https://www.amazon.com/Valvoline-Sy...ocphy=9028241&hvtargid=pla-560457971477&psc=1
doesn't say GL-4, but it does say "Fully compatible with yellow metals including copper, bronze and brass". And it is $7.99 a quart on Amazon.

 

Thanks Bill I’ll check it out.