Dodge Caravan brakes

[cheap 40]

OK, '02 Dodge Grand Crapavan w/about 105K miles - when stopped in gear with brakes applied, the brake pedal slowly drops to the floor. If stopped at a long light, it starts to get interesting (difficult to keep still). Braking system has NEVER been opened, so I'm 99% sure that this is not an issue of air in the lines. I'm thinking that the master cylinder is blowing by internally (no leaks visible).

Before I start throwing $$ at this turd, I figured I'd get the collective opinion of Mud. What say ye? MC toast?

Thanks

Tony

 

[Gumby]

It's 95% it's the master cylinder.

Many times a bad master will pump back up, then sink back down.


If it's sinking and you're not losing fluid, I'd throw a master at it.

I've seen LSPVs do that as well, but not often and I doubt you have one on the caravan.

 

[35inchoverdrive]

Since you said that the system is never been opened, that means you've got 6 year old brake fluid in there. It's probably got a substantial amount of moisture in it. In the interest of saving money, you could just try bleeding the brakes enough to flush all the old fluid out, and see if that helps. Also, if there are no visible leaks from the MC, I would unbolt it from the booster, and see if it's leaking into the booster. That's not an uncommon way for it to fail, and it will toast your booster eventually. I would agree, that it is probably just a bad MC, but a thorough brake bleeding and visual inspection of the inside of the booster could help confirm, or dismiss the diagnosis.

 

[cheap 40]

I'll pick up a MC and inspect/flush everything while I'm in there. Thanks!!

Tony

 

[cruiser88]

It's 95% it's the master cylinder.

Many times a bad master will pump back up, then sink back down.


If it's sinking and you're not losing fluid, I'd throw a master at it.

I've seen LSPVs do that as well, but not often and I doubt you have one on the caravan.

Is there a check valve that goes into the booster?