Dot 5

[edison1970]

I have had reoccurring brake issues from day one with my car. All new, nothing used. Day one, excellent pedal feel. Nice and firm and almost too touchy.  Days later,  pedal spongy.  Bleed brakes again. Works great. A week later, soft again. I assumed a leak and I found a few fittings seeping.  Fixed that and bled. Well you probably guessed it that it didn't last. When I  pulled the master cylinder off,  it was leaking from where the push rod goes in. Replaced the master and it is leaking again from the back of the master. Are the new rubber seals not compatible with dot 5? Has anyone else had this issue?

[GoodysGotaCuda]

I have been using it and have not run into any issues with leaking, it's been a few years now.

I did have issues initially bleeding it because air suspends so much in it, you don't want to pour the "bled"/fresh fluid out then pour it back into the master as you cycle through it. Leave any "bled" fluid to sit overnight before putting it back, assuming everything is new and there's nothing wrong with the fluid coming out.

[anlauto]

I use Dot 5 in all my restorations 

[Chryco Psycho]

Never a problem using Dot 5 fluid , maybe buy a seal kit for the cylinder you have & rebuild it with the best seal kit yo can buy , Raybestos , Wagner , Carlson are good names , Rock Auto probably sells a kit .

[Jay Bee]

My master cylinder and wheel cylinders were replaced in 2011. Flushed and re-filled with Dot5. Other than 2 rear wheel cylinders going bad/leaking in 2014 I haven't had an issue since.    

[Banana]

I've had lot's of frustrating leaks due to using stainless steel lines (stainless much more difficult to seat at the fittings), and crappy repro distribution blocks (finally had my originals rebuilt), but thankfully I decided to go with DOT 5 and I avoided massive paint damage.

DOT5 gives a slight sponginess to the system, but the brakes work.

[edison1970]

I've used dot 5 in all of my motorcycles in the past with no issues. I actually think this is the 3rd master for this car. They all did the same thing. Excellent pressure that lasts for a week or so then the pedal gets soft. Each one leaked from the back of the mc. I'm sure these are made in China.  Maybe they are using inferior seals? I have been draining the system over the past few days.  Brake cleaner in the lines and calipers then hit with compressed air. Going to do the rears tomorrow.