View Full Version : Brake fluid dot 3,4,or 5?

10-30-2014, 3:52 PM
Rear drum juice brake whats the consensus dot 3 4 or 5?

10-30-2014, 4:03 PM
Rear drum juice brake whats the consensus dot 3 4 or 5?

What master cylinder?

You need to run 5 in the stock Wagner.

But then again I'm assuming you're talking about a Harley...

10-30-2014, 4:37 PM
3 and 4 are essentially the same. at the factory 76 up to mid 2005 used dot 5 before that dot 3.

10-30-2014, 5:42 PM
Yeah its a 69 FL the cap on the master says 5 but I no theres either 3 or 4 in there. Its the stock master I think it is a wagner. Question is if I have 3 or 4 in it can I flush it out and replace it with 5?

10-30-2014, 5:51 PM
You can flush it thoroughly. It's probably better to run the 5 in there to avoid any long term damage the 3/4 will do.

10-30-2014, 5:56 PM
What can I flush it with?

10-30-2014, 6:23 PM
Denatured alcohol I'm told. I've had everything torn apart and just used brake cleaner before then blew it out with compressed air.

10-30-2014, 7:11 PM
So I would have to take apart the master and brake cylinder?