Opinion on using DOT 5 in non-ABS cars?

[Xiao_Hu]

So I haven't had to do anything to the brakes on my car yet, thank Ishtar everything has "just worked" outside of the motor problems. However, when the time comes to rebuild the brake system which I know will happen for an old car like this, what's the current opinion of you guys using silicone based DOT5, not 5.1 or 4 glycol ester stuff? 

 

I have a friend who is in his 80s and drives a 1978 Corolla that looks like shit but drives perfectly. He swears that he hasn't touched the brakes in 30 years and credits using silicone based Dot 5 and cupronickel lines when he ran the brake lines last. He's had to replace pads and such obviously but not had to touch the hydraulics at all. He did the same thing with his clutch as well. 

 

Is there any truth in what this old curmudgeon is telling me or is it overblown? I'm not asking for people who haven't done it necessarily, more so for people who have done it. 

[MikeRL411]

DOT5 is silicone based; it is compressible [due to its long chain molecule] contrary to assumptions that fluids are non-compressible. So, it is "mushy" feeling. If you can get by that, alright! It is non hydroscopic so will not adsorb water, vapor or liquid, which is its advantage.

[Duncan]

I used it in a 510 wagon and had no problems.  A big plus is it doesn't damage paint if it gets spilled. 

 

I did not notice a squishy pedal, but it was not a race car, either..

 

 

[fiveoneO]

I mainly use Dot 4 and have never had an issue, but after reading what Mike and Duncan said about Dot 5, I may give that a try.

[datzenmike]

DOT 3 is fine if you replace it every 30k but no one does and there's problems. Longer life comes with compromises I guess. Reminds me of the kid who goes into store and demands the absolute best performing brake shoes made for his car. Guaranteed to stop in half the distance over the OEM pads. Put's them on and the next day while speeding piles into the back of a semi. Goes back and complains to the counterman. 'Well they are metallic pads, you got them good and hot before using them didn't you??????? '

[Xiao_Hu]

My biggest issue with glycol fluids is they eat seals, especially on cheaper parts, much faster. 

[Duncan]

I never thought about brake lines, but I had a mixture of old and new lines on my old wagon.  I also used a 210 brake booster for power brakes.  I drove it for about three years prior to selling it, and never had a problem.  Again, just my experience.

 

 

[datzenmike]

3 hours ago, Xiao_Hu said:

My biggest issue with glycol fluids is they eat seals, especially on cheaper parts, much faster. 

 

I don't think that's the case. All 'rubber' parts are rubbing something and that's the wear.