T15 & Dana 20 Oil To Use

Going to begin the rebuild process of my T15 trans and Dana 20 Transfer case. I purchased the Novak Master rebuild kits. I notice on Novak site that they "recommend" mineral oil or 50w conventional engine oil.

I also purchased the Novak deep pan for the Dana20 that add about 16oz additional lube.

I already purchased a gallon for 85w90 GL4 gear lube and wondering what fluids you guys have put in your T15 and Dana20.

Reason for rebuild is popping out of 2nd and reverse. I don't know what the gears look like yet but the master kits for both include everything else.

 

The GL4 will work fine, safe for yellow brass and it's what most people use.

 

It's what I use
https://www.amazon.com/CRC-Sta-Lube-SL24239-Multi-Purpose-Hypoid/dp/B000M8RYMC/ref=sxts_rp_s_a_1_0?content-id=amzn1.sym.eff26b9b-e255-411b-a40d-eccb21f93fe4:amzn1.sym.eff26b9b-e255-411b-a40d-ec
It aint cheap

 

Yes 3b that is the lube I bought and will go ahead and use. thanks