Considering switching to dot 5 brake fluid

[deltabronco]

I am considering switching to Dot 5 due to Dot 3 is destroying my paint. I initially thought I had fixed the leaks in my brake system only to find another by the front driver side tire. In the process it has started eating the paint off the chassis and shocks. Has anyone flushed the system and cleaned ( or replace) components so the dot 3 could be changed out to Dot 5???

 

[Viperwolf1]

Wouldn't be easier to just fix the leak? I mean you're probably going to want it to hold dot 5 too, right?

 

[deltabronco]

I thought of that, and yes I'm going to fix the leak. But for some strange reason leaks seem to be reoccurring on this vehicle. I fix one and another begins to leak. Getting a bit frustrated.

 

[Rustytruck]

If your getting leaks in your brake lines. try backing off and tighten the lines several times to seat the fittings. also are you using the proper line fitting wrenches so you can get them really tight. There's allot of pressure in those little lines and even more so if you run hydroboost.

 

[SteveL]

I thought about doing it until I read up on dot 5. Any contaminants such as water and dot 5 goes bad. Dot 3 is like a cockroach. It just keeps working. I would change out the lines or whatever keeps leaking. The brake system is the last thing I would want leaking on a rig

 

[Apogee]

I don't like DOT5 fluid, as it tends to be more viscous and doesn't produce as firm a pedal as the Glycol based DOT3/4/5.1 fluids in my experience. The only thing I would run DOT5 in would be a museum piece that saw the occasional parade or something similar. You should be able to avoid any plumbing leaks, leaving only the MC as the wild card as far as leaking in the future. Once brake lines have been properly seated, they shouldn't leak, and over-tightening them is not the solution. Clean, symmetric flares should do the trick with minimal torque on the tube nuts.

 

[deltabronco]

What about the proportioning valve? I am having issues with the line leaking underneath the front of the valve.

 

[DirtDonk]

And if it's an aftermarket type (brass block thingy) you might want to make sure that any fluid you see dripping from the bottom is not leaking out of the delay valve under that rubber boot at the end.

Paul

 

[deltabronco]

You have a brake line connected to the bottom, front port of the proportioning valve?

Yes.

Paul, none is leaking from the button.

 

[jason_marshall1]

I was wondering the same thing except for my old corvette. For what it's worth, this is a decent article talking about the pros and cons of dot5. They specialize in corvettes, but the principals are the same. https://www.muskegonbrake.com/corvette/converting-silicone-brake-fluid

I was rebuilding my master cylinder and found one kit supplier that said the warranty was void if dot5/silicone fluid was used so I decided not to pursue the switch further; just seemed like there was too much unknown or uneasiness with it for me. Of course, I can't find that site/link now with details.

 

[deltabronco]

From what I have read there are plus and minus for each side.

 

[deltabronco]

2 lines go in the top, one in rear and one under the front...

 

[deltabronco]

Yep, that's it