What is the best rear diff fluid to go with.everone is tellin me royal purple 75w140 but I know ford recommends 80w90.what do you guys suggest?I have a 98 cobra stock rear end no gears
Best rear diff fluid on my 98 cobra?
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I don't like royal purple for rear diff fluid. I bought Amsoil 75-110 and I've heard great great things about it from other people all over the net. I have been very happy with it so far. Mixed it with Motorcraft friction modifier and was good to go.
I've never been a big fan of the royal purple products. However, +1 on Amsoil products. I used Amsoil and the ford friction modifier (you can get gear oil with the addative already mixed with it) but just for added protection I did it anyway.
I run Amsoil with Ford friction modifier in my 03
Amsoil and modifier in mine. not a fan of RP either..or Redline for that matter.
Same with the Amsoil and modifier for me.
Mopar Synthetic 75W140 and Ford FM in mine. Its either Mobil or Shell/QS/Pennzoil or another company that supplies Mopar with their fluids.
Any synthetic 75W140 with friction modifier will work good.
Any synthetic 75W140 with friction modifier will work good.
Pretty sure its Shell. Mopar is a middle of the road fluid. I wouldn't use it.
Royal Purple is the most unstable gear oil you can buy. Even worse than Lucas. Both have been shown to lose 35%+ of their viscosity after shear testing.
Amsoil and Redline sheared only 3-5% in the same test.
Royal Purple is the most unstable gear oil you can buy. Even worse than Lucas. Both have been shown to lose 35%+ of their viscosity after shear testing.
Amsoil and Redline sheared only 3-5% in the same test.
The Mopar branded stuff was free, I cant complain.
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