changing dot 4 to dot 5
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- xpress
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changing dot 4 to dot 5
i want to change to dot 5. i just don't fancy having to bother with the dot 4 and replacing it etc.
if i drain it out completely can i just fill up with dot 5, or do i need to do something else?
if i drain it out completely can i just fill up with dot 5, or do i need to do something else?
Das AutoWagen.
- ronsrecord
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Re: changing dot 4 to dot 5

think i've had too much to drink already!!
Making hay while the sun shines!
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2.1MV Club Joker, 1988, LPG/ petrol
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Re: changing dot 4 to dot 5
erm i wouldnt know but why areyou changhing it ? got a free bottle off freecycle? but i,d suppose drain flush would be ok but i dont know ,bump 

- dugcati
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Re: changing dot 4 to dot 5
As far as I'm aware the main differences is in the boiling point of the fluid - DOT5 should have a very high boiling point as far as I understand it....
It is by will alone that I set my 'van' in motion!
- xpress
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Re: changing dot 4 to dot 5
oh hiya biz m8, i need a new caliper front n/s! bummer eh.
Das AutoWagen.
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Re: changing dot 4 to dot 5
last time i did dot to dot it turned out to be a horse, then me pencil broke. 

john & jenny
1979, cu devon.
1979, cu devon.
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Re: changing dot 4 to dot 5
Damn - THATS what it was. Unfortunately I went from 13 to 42 by accident and it came out as some kind of gardening implement. Horse eh? Damn...
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- SyncroSwede
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Re: changing dot 4 to dot 5
xpress wrote:i want to change to dot 5.
No you don't. You want to change to DOT 5.1. DOT 5 is silicone based not glycol based and is for specific systems only as it will swell seals on DOT 4/5.1 systems.
I'm not an expert but I don't think mixing 4 & 5.1 is a problem just a little pointless as you will not get the full benefits of the new fluid. Personally, I would not drain and flush but bleed through the brakes & clutch as per the manual until nice clean fluid comes out, run it through the winter then do the same in the spring. Just me though...

1989 16" Syncro 2.1l WBX… replaced by a 2010 T5 GP
- xpress
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Re: changing dot 4 to dot 5
i might use this 5.1 stuff.
how cheap can i purchase thsi amazing 5.1?
how cheap can i purchase thsi amazing 5.1?
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- SyncroSwede
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Re: changing dot 4 to dot 5
Halfords DOT 4
Halfords DOT 5.1
I had DOT 5.1 in then I used DOT 4 when I had to top/bleed when I replaced the clutch slave. The DOT 4 was good quality (Wurth) but was free and like I said, they're compatible so on these vehicles I think either is fine.
Halfords DOT 5.1
I had DOT 5.1 in then I used DOT 4 when I had to top/bleed when I replaced the clutch slave. The DOT 4 was good quality (Wurth) but was free and like I said, they're compatible so on these vehicles I think either is fine.
1989 16" Syncro 2.1l WBX… replaced by a 2010 T5 GP