Brake Question Lockheed 55

Hello, everybody.

I'll ask you about one of my second cars. Maybe someone might have guessed.

My (high-)summer car is a Simca Chrysler 2 liters bj 1973. I'll probably know the few of you, but I'm still going to continue writing...

the thing has a single-circuit braking system with nem Lockheed HBZ. I bought the car four years ago. I've been driving 500 km since then and had the 4 HBZ installed last week... And I'm starting to run out of dinger... the problem is that the membrane leaks. At first I thought, well, the rubbers are 30 years old but so slowly one should be good, especially since the last 2 were still original packed

Now the mechanic of my trust asked me what kind of brake fluid was coming in... he read in the manual that "lockheed 55" is required... and what this is or what the successor means...

So far we have always taken DOT 4. But the last membrane was probably not porous, but raised or lowered. Resolved...

well, I thought. I would ask another mechanic (one who has been representing a simca / Peugeot since 1969) and who is really familiar with these things. But look... he said DOT 4 you've always taken. There was probably a blaue of fluid that didn't get along with others but that was a problem until the mid-sixties. I don't think I'm gonna do it after that.

is also funny, which probably the membrane of the HBZ liquid does not become but the rubbers of the wheel brake cylinders...


Any of you guys have any idea what's going on?? or which product has been replaced by lockheed 55??