synthetic multigrade gear oils are expensive - even more expensive than engine oil.

since asa pinas naman tayo kahit monograde na gear oil pwede. just take note that if the manufacturer says gl4, use gl4 NOT gl5 unless its compatible with gl4.

monograde gear oil such as spirax g sae90 (gl4) costs iirc 1xx.xx+/L while rp max gear 75w90 costs 8xx.xx/L