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Discussion Starter · #1 ·
What's the difference between the various DOT fluids? I know that Avid suggests DOT 4 or 5.1 to bleed my Elixirs. But in my haste at the hardware store, I grabbed DOT 3. Is this a huge difference? Are my brakes gonna start on fire? :madmax: I was hoping to get them done tonight, since I don't have any time over the weekend to go back to the store. Is the DOT 3 fluid acceptable or should I wait and get the right stuff?
 

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I would get the right fluid.. I think the wrong dot fluid can damage the sills in your cylinders. That would be bad.
 

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DOT 3 was used in older cars etc. 4 just has a higher boiling point and lasts longer. 5.1 was designed for modern cars with ABS it is higher performance than 4 but adsorbs water quicker. Provided your not doing extreme downhill or anything 3 should be OK but I would change to 4 when I can. Of course I may have it all wrong.
 

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Yeah they are all based on polyethylene-glycol and the significant difference is their boiling points. I would put in dot 5.1 bc there is less chance you will roast you brake fluid. but yes technically dot 3 will work just poorly
 

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I somewhat understand the differences between DOT 4 and DOT 5.1, as the others have noted, and both will work fine with your Avid brakes. But I think the key here is that Avid specifically states it's either one of those, not DOT 3 (nor 5.0), so I would wait and get the proper fluid.
 

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Discussion Starter · #6 ·
onegymrat said:
I somewhat understand the differences between DOT 4 and DOT 5.1, as the others have noted, and both will work fine with your Avid brakes. But I think the key here is that Avid specifically states it's either one of those, not DOT 3 (nor 5.0), so I would wait and get the proper fluid.
Well, I did some research on it. Dot 3 is the same stuff, just formulated with a lower boiling point. In a pinch it will work but not recommended and will most likely burn up. DOT 5 is a big no no since it is a different substance entirely. I believe it's silicone based. But, for the record, I did wait and found DOT 4 at NAPA and grabbed that. So I'm all good:thumbsup:
 

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I have Juicy 5 brakes which specify DOT 5.1. I grabbed some DOT 5 fluid at the auto parts store.

The 5.1 is carmel in color, and the 5 is purple. The DOT 5 says that it can be added to fluid that is already there, but I added them in a bottle, and they don't seem to mix. The carmel stays at the bottom and the purple is at the top.

Should I just go back and find some SRAM DOT 5.1?
 

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Discussion Starter · #8 ·
Ferdball said:
I have Juicy 5 brakes which specify DOT 5.1. I grabbed some DOT 5 fluid at the auto parts store.

The 5.1 is carmel in color, and the 5 is purple. The DOT 5 says that it can be added to fluid that is already there, but I added them in a bottle, and they don't seem to mix. The carmel stays at the bottom and the purple is at the top.

Should I just go back and find some SRAM DOT 5.1?
Yes sir. Do not put that in your lines. Dot 5 and Dot 5.1 are way different. You would think that they would not name them so alike with the major differences. I would think Dot 4.1 would make more sense since it is the same stuff just with a different boiling point. The DOT 5 is silicone based and the DOT 5.1 is polyethylene-glycol. Not the same stuff. :nono:
 

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3fast3furious said:
Yes sir. Do not put that in your lines. Dot 5 and Dot 5.1 are way different. You would think that they would not name them so alike with the major differences. I would think Dot 4.1 would make more sense since it is the same stuff just with a different boiling point. The DOT 5 is silicone based and the DOT 5.1 is polyethylene-glycol. Not the same stuff. :nono:
Whew! Thanks for your reply. I have sone 5.1 from Finish Line on order.
 
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