Dot 5

[rudi dudi]

Does anyone know or maybe has done so by using DOT 5 ( not to be confused with dot 5.1) in our 850's or 70's
Dot 5 being silicone based and is hydraphobic.It is used a lot in classic car circles and vehicles that are laid up for long periods.
These in general do not suffer from sticking calipers etc due to the use of Dot 5.
Im not interested in boiling point etc stats but more compatibility issues with the rubber components in the braking system and abs pump.
Cheers

[850Red]

No. But I do know that it doesnt like mixing with Dot4 at all. Not sure how you'd flush it completely, could be a bit of a nightmare.

I used Dot5.1 in my T-5R. Just because.

[volvo again]

https://cartreatments.com/compatibil...5-brake-fluid/

you probably already know this...but thought it might help and as 850red says, not sure how you would make certain all the old dot 4 is removed

[Luxobarge]

I use it in my classic MG Midget, but didn't have a flushing problem as when I restored it the entire braking system was new. I decided to use it as this is an example of a car that is laid up for long periods, and in terms of not corroding the cylinders and calipers etc. it works well. However, it's not without its problems, it does tend to swell the seals a little, and it doesn't naturally lubricate the bores and seals as well as conventional fluid. This means that the pistons can get a bit sticky in the bores, the rear drum brakes are fine but I've found that the disk calipers at the front don't retract fully when releasing the brakes, so there is always a bit of residual drag on the brakes. Also the clutch slave cylinder doesn't like fully retracting, so it tended to leave a little pressure on the clutch mechanism, which eventually wore out the thrust bearing. To cure this I had to rig up an additional return spring to pull it fully off.

Because of the above, my personal view is that I'd only use it on cars that are going to go LONG periods without use, and even then only if I could find a way of thoroughly flushing the system, and I'd be checking very thoroughly for the above type of problems. Anything else, I'd use conventional fluid, and just flush it through more often to maintain its quality, less hassle in the long run.

HTH

[rudi dudi]

Cheers Guys