Best 85w-140 dino gear oil?

[north1]

Looking for a high quality GL5 85w140 dino gear oil for the differentials and planetaries of a 575 horsepower versatile 4wd tractor. Have used viscosity oil co and mobil products in the past. 85w140 is recommended over 32F, 80w-90 under 32F and this tractor is a spring, summer and fall workhorse so I think the 85w-140 would be recommended.

 

[Slick17601]

Shell Spirax or Pennzoil Gearplus would work well.

 

[beanoil]

Chevron Delo ESI. Great performance, unique Borate composition.
http://www.deloperformance.com/products/gear-lubricants.aspx