Mechanics

DODGE CARAVAN BRAKES PROBLEM

2002 Dodge Caravan • 175,000 miles

2002 Dodge Grand Caravan brakes are not releasing, changed calipers, pads, brake lilnes and master cylinder also flush out brake fluid. Any ideas on where to go from here?
AD
Avatar
Johnhaataja
October 22, 2012.




When they lock up, crack open the steel lines at the master cylinder to see if any trapped fluid pressure releases.

Caradiodoc
Oct 22, 2012.
Have tried loosening lines at master cylinder but doesnt help brakes are still dragging enough that they will get hot enough to start smoking

Tiny
Johnhaataja
Oct 23, 2012.
That is tentative good news as it does not definitely indicate brake fluid contamination. That is an expensive problem.

Open the bleeder screws on the calipers to see if they release. If they do not, the pistons are sticking in them. If they do release, suspect the rubber flex hoses. I suppose there could be internal leakage in the anti-lock brake hydraulic controller if you have ABS but that's not really a problem I've heard of.

Caradiodoc
Oct 23, 2012.
Thanks for the suggestions! When breaking lines at the caliper the brakes do release and have put new lines at the wheels
AD

Tiny
Johnhaataja
Oct 23, 2012.
Do you have anti-lock brakes?

Caradiodoc
Oct 23, 2012.
Yes it has antilock brakes

Tiny
Johnhaataja
Oct 23, 2012.
Go all the way up to the hydraulic controller and crack open the lines to see if the brakes release. If they do, I suspect this might be one for the dealer. Unlike some older systems, there is no brake fluid stored at high pressure so leakage in a valve shouldn't be a problem, however, I suppose a valve could be blocked and not allowing the fluid to go back to the master cylinder.

The base hydraulic system is still a split-diagonal design with the two front brakes on different circuits. They each also have their own circuits during an ABS stop. That would imply there would have to be two blocked passages in the controller or a blocked passage that is common to both front wheels. That's assuming, of course, that both front brakes are locking.

This isn't something I've run into before. I hope I'm wrong about it needing a controller.

Caradiodoc
Oct 23, 2012.
Just changed the abs unit with one from salvage yard and bleed everything went on test drive and brakes not any better will be starting over tomorrow

Tiny
Johnhaataja
Oct 30, 2012.
When you said you replaced the lines, I assumed you meant the rubber flex hoses. Is that right or did you mean the steel lines?

When a caliper is locked up, start up higher, like by the controller, and crack something open to release the trapped brake fluid. Work your way down until you find the point where it releases. That will be the point of the restriction. If you find a metal bracket crimped around the middle of a flex hose, that is where rust likes to build up and constrict the hose. Peeling that crimp open just a little with a large Channel Lock pliers will solve that one.

Caradiodoc
Oct 30, 2012.

AD