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dot 3, 4 and 5.1 are glycol-based and can be mixed. they are hygroscopic and absorb water. more water absorbed means lower boiling temps and rust which is why you need to change em every now and again.
difference between the specs is the boiling point it can cope with. 5.1 being higher.
mixing 5.1 with say 3 will reduce the boiling point
3, 4 and 5.1 are synthetic glycol based (which is why you can mix em).. you can get mineral or silicon.. but they are not the norm.
5 is a different beast. it is silicon based and is not hygroscopic. it's not generally wise to use it as water can get trapped in the system and cause issues.
but you are driving a series, you are never going to boil the brakes up (unless the fluid has absorbed loads of water).. so bung in the cheapest 4 or 5.1 and move on
(3 would probably be fine too, but there's no real price difference)
difference between the specs is the boiling point it can cope with. 5.1 being higher.
mixing 5.1 with say 3 will reduce the boiling point
3, 4 and 5.1 are synthetic glycol based (which is why you can mix em).. you can get mineral or silicon.. but they are not the norm.
5 is a different beast. it is silicon based and is not hygroscopic. it's not generally wise to use it as water can get trapped in the system and cause issues.
but you are driving a series, you are never going to boil the brakes up (unless the fluid has absorbed loads of water).. so bung in the cheapest 4 or 5.1 and move on
(3 would probably be fine too, but there's no real price difference)
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