Decided to look at the oil in my differential this afternoon.Car has 121k km on clock(say 76k miles).

1.Jacked up rear of car and placed jack stands per JTIS.
2.Removed fill plug using 3/8 ratchet,came easily.There is no drain plug.
3.Removed old using my Valvoline oil pump.Got about 1.25L out.Oil was dirty.
4.Cleaned the oil pump and inserted 1.25L of clean Ford 75W140.
5.Lowered car and allowed excess oil to drai from fill plug.
6.Installed fill plug.

 

How's everything with the fluid change? I will be doing this in a day or two, just wasn't 100% on which lube I was going to use, the one you did, or something 80/90.

 

Its OK thanks.My Owners Manual says 75W140,and the Ford product is full synthetic and is the same spec.
I used Castrol Syntec 75W90 in my RX7s,both gearbox and diff.I tried the 75W140 and it was too heavy.
When I worked at the local Mazda dealer the recent Ford based products,trucks and SUvs all used the 75W140 product in the diffs.
I think Quaker State also have a 75W140 full synthetic.

 

A necessary fluid change at 70k+ miles.