2008 Toyota Tacoma, 114,500 miles: open front differential, Mobil-1 75W-90, GL-5. Rear Differential w/Detroit True/trac, Traveller (Tractor Supply) 80W-90, GL-5 which is a mineral base oil, without friction modifier/LS additive, as recommended by Eaton. 30,000 on front diff. since change and 100...