Need some help with gear oil recommendations for my AWD EcoBoost Ford Flex.
The factory fill rear differential fluid is a dino 80w-90 Motorcraft XY-80W90-QL conforming to the following specs: MIL-PRF-2105E, Mack GO-J, WSP-M2C197-A, GL-5 and MT-1 specs.
I also need a replacement fluid for the PTU (power transfer unit or transfer case). The factory fill PTU fluid is synthetic 75w-140 Motorcraft XY-75W140-QL conforming to the following specs: WSL-M2C192-A, GL-5.
What would be better options (if any) to replace the factory fill? I think I'd like to go with synthetic oils in both units.
Also want to stick with the OEM spec'd 80w-90 weight in the rear differential (will not consider a 75w-90) since the cold viscosity is so much lower (from 7.0 cSt to 4.1 cSt minimum) when going down from an 80 to a 75.
Lastly, I will not consider any "boutique" oils which are not certified to meet a certain spec while claiming that it meets or exceeds the performance of the spec. I am personally not comfortable with using oils which are not certified. I believe this requirement will eliminate the likes of Amsoil and Redline for example.
Thanks in advance.
The factory fill rear differential fluid is a dino 80w-90 Motorcraft XY-80W90-QL conforming to the following specs: MIL-PRF-2105E, Mack GO-J, WSP-M2C197-A, GL-5 and MT-1 specs.
I also need a replacement fluid for the PTU (power transfer unit or transfer case). The factory fill PTU fluid is synthetic 75w-140 Motorcraft XY-75W140-QL conforming to the following specs: WSL-M2C192-A, GL-5.
What would be better options (if any) to replace the factory fill? I think I'd like to go with synthetic oils in both units.
Also want to stick with the OEM spec'd 80w-90 weight in the rear differential (will not consider a 75w-90) since the cold viscosity is so much lower (from 7.0 cSt to 4.1 cSt minimum) when going down from an 80 to a 75.
Lastly, I will not consider any "boutique" oils which are not certified to meet a certain spec while claiming that it meets or exceeds the performance of the spec. I am personally not comfortable with using oils which are not certified. I believe this requirement will eliminate the likes of Amsoil and Redline for example.
Thanks in advance.
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