4BW Rear Differential Fluid

[Raskolnikov]

For anyone who has changed the diff fluid in their 4bw: a little research has suggested that I should use

75w-85 SAF-EH Modified Low Viscosity Rear Axle Lubricant - 1 qt - GM (19418501)​

Can you please confirm that this is the correct fluid? GM wants $75.00 per quart!!! Is this made from unicorn tears?

 

[mfcentex]

I used ACDELCO 10-4131 from Rock Auto about 2 months ago.

 

[Sergio]

I got 2 qts from the Chev dealer. Asked for a discount and I think it was $46 a qt.