Reproduction Master Cylinder... silicon DOT 5 ?

[Jim D.]

Re: Reproduction Master Cylinder... silicon DOT 5 ?

The DOT 5 in my 60 has been in there since 1986. It's still purple and I've had zero brake issues. That being said, I just bought 4 SS sleeved calipers and they came with the warning not to use DOT 5 or the warranty will be void.

[Terry M.]

Re: Reproduction Master Cylinder... silicon DOT 5 ?

Is there is need to change the brake fluid over a certain period of time when using Dot5 Fluid? I have been running Dot5 in my 66 for 10+ years with no problems, just wondering about need to change/flush system? thanks

I had DOT 5 in my 1970 for +/-20 years. I changed it just because it bothered me not to. That was over a decade ago, and I don't expect to do it again. The next custodian can decide what s/he wants to do regarding DOT 5 brake fluid.

[Gene M.]

Re: Reproduction Master Cylinder... silicon DOT 5 ?

I had DOT 5 in my 1970 for +/-20 years. I changed it just because it bothered me not to. That was over a decade ago, and I don't expect to do it again. The next custodian can decide what s/he wants to do regarding DOT 5 brake fluid.

Hey Terry,
Have you noticed when do any of the changes that the dot 5 lost it’s purple color?

I’ve seen some that becomes clear almost.

[Duke W.]

Re: Reproduction Master Cylinder... silicon DOT 5 ?

In my experience the purple die fades out with age, but that has no effect on performance... just identifying the type of fluid.

Duke

[Terry M.]

Re: Reproduction Master Cylinder... silicon DOT 5 ?

In my experience the purple die fades out with age, but that has no effect on performance... just identifying the type of fluid.

Duke

I have noticed the DOT 5 I have (STP Brand) that is nearly as old as the Corvette has long ago given up its purple hue. That doesn't bother me and it seems not to bother the function of the brake fluid either. I know Gene knows, but for Duke I must provide full disclosure that the days of my spirited driving in the 1970 LT1 are past for car reasons. It wears Goodyear Speedway Wide Treads that are as old as it is. It goes out only very occasionally and only under very close adult supervision. It was out for Kansas City National in 2015 and this last Summer for a rendezvous with ALL the Corvettes I have ever owned. My 1969 has resurfaced and that event will merit a story for Vinnie and The Restorer. (Soon Vinnie. Stay tuned.) Its next outing will be for the year of the 1970 in French Lick in 2020. Other than no brake fluid leaks I am not testing the limits of the DOT 5.

[Domenic T.]

Re: Reproduction Master Cylinder... silicon DOT 5 ?

I posted a few times, but one day I needed my old fork lift and the pedal went to the floor. about every 6 Months it needed about 3 OZ dot 3.
I was in a pinch and another mechanic said, "well if your going to replace the whole brake system, what have you got to loose by adding the dot 5 you have".
I did, about 5 years ago, system works great. with the mix. I would never do that with a pass car but, my fork lift speed is so slow that the mechanical brake will stop it so it wasn't a problem.
Then my tug that I use once a month did the same thing a few years ago and I added old dot 5 I had and it is working.
I know if put in a glass you would see the seperation, but HEY, Iv'e been on borrowed time for years with no problems.
I did change my 67 coupe over to dot 5 and did a flush and another flush after flush then blew the system with nitrogen to blow the flush out.
I have standard brakes, (no power) and found that my pedal felt stiff and even though the brakes worked well, it didn't feel right. Pedal only went down less than half the way it did with dot 3?
I will use dot 5 again in my 67 with the all new system and hope it feels better. And no the brakes were not partially on all the time.

Dom