Castrol EPX-90 for rear axle, Opinions?

[FCD]

Just bought another liter of this stuff to have the diff oil changed tomorrow.

Product Performance Claims
API GL-5
MAN 342 M1
MB-Approval 235.0
ZF - TE-ML 16C, 17B, 19B, 21A

Since my Capri specs EP 90 for the axle, and nowadays 90 grade oils have a thinner maximum viscosity than in 1975 i sought after a thick ish EP 90, this is 17.0 cst @ 100c ( most i found only had 15 or so ), 195cst @ 40c and the VI is 97.
I'll also have the gearbox oil changed with genuine Ford 75W-90 GL-4 Mineral oil.
What does BITOG think of this oil?

 

[zeng]

Pre-1998 SAE 90 specifications has been split into present day:
a)SAE 90 of ISO 150/AGMA 4EP with KV@40*C range of 135-165 cSt; and
b)SAE 110 of ISO 220/AGMA 5EP) with KV@40*C range of 198-242 cSt.
Castrol KV@40*C of 195 cSt is within spec but Ford 75W90 of KV@40*C 76 cSt is not.

 

[FCD]

My main concern is yellow metal compatibility, i'm sure the genuine Ford gearbox oil will be fine, surely it's better than the mineral SAE 80 they used in the 70s.

 

[Y_K]

This particular Castrol oil is hard to find in USA. Mono 90 is a rare bird here. As another thread here demonstrates, most folks are not aware of the differences between multi and mono 90 gear oils here. I used Motul and Lubrication Engineers in past for F-350 and Landcruisers.
Tha Castrol looks solid.

 

[FCD]

Well, i just changed the oil and the oil that came out of the diff looked like crude oil, seriosuly thick and goopy and black like coal, the gearbox seemed to have been overfilled with il the last time, and the oil seemed fairly thin.

 

[zeng]

Care to elaborate further ?

 

[FCD]

What do i need to elaborate on? basically i am glad that i changed the oil because the diff oil was in very bad shape, thick and black like coal, the oil that came out of the gearbox looked brown and it seems like it had been overfilled the last time.
The gearbox feels better after changing the oil, gear changes seem a bit smoother.