DFD536

I was driving to work this am, and the brake pedal seemed to get higher (not physically, but the brakes would activate much higher than normal when pressing the pedal). By the time I got to work, it was like the brakes were being slightly applied. So, I get out of work, everything seems normal, but as I am driving home, the brake pedal rises again, until the brakes are very obviously being applied. I stopped, and called the dealer, who was at a loss, but said since the power steering supplies the hydrolic assist to the brakes, maybe it was low and allowed an air bubble in. I checked, it was low. I added some, and things got worse. I was actually spinning the rear tires to push the locked brake truck into the pk lot. i tried several times turning the wheel, hitting brake pedal, etc with no relief. As a last ditch effort, I loosened the bleeder on the brake caliper, and the fluid sprayed half way accross the parking lot (much further than when you bleed the brakes), everything seemed to work normally after that. I drove towards home, and things got worse again. What on earth could be causing this, and short of bleeding pressure off every few miles, what can I do?
Thanks,
Dennis

Totallyrad

Is it just the front brakes that are applying?

Have you recently serviced the front brakes?

DFD536

sorry for the late reply, no brake work done in months, then it was the rear, system pressure bled, now calipers on both rears... I got it home, and it seemed everything was working fine, but it has done it again since.. again, bleed it off and it's fine... can't figure it out...

DFD536

Since I'm no longer stranded, I'm going to move this to the normal area instead of the help section... please look it up there ! Thanks,
Dennis

Totallyrad

There's a possibility either the flexible lines at the wheels are collapsing or the ABS is malfunctioning.

DFD536

I hadn't thought of the abs unit... lines look ok from the outside, do you know how I would check them? I am not familiar enough with the ABS unit to know how it applies, whatever this is seems to be gradually introducing pressure into the front brake system continuously, when I bleed it off, it works normally for a while, then as the pressure exceeds the amount of extra room in the system, it simply starts pressing the calipers shut. It is almost like introducing extra fluid/pressue from somewhere (nothing leaking that I can tell, power steering fluid is still full from first fill)...

DFD536

I don't know how to post a link, but I have started a thread here in the non-emergent part, titled "Ghost brakes! applying themselves while I try to drive" Thanks!

Shorts

I had never heard of brake hoses collapsing but apparently they do. I've heard it several times in the past year from Dad on his 2gen. When the hose collapses it does make the caliper stick/apply brakes. Then you've got brake drag and your pad wears very fast.

A collapsing hose would fit this description.





From what I heard from Dad "I replaced the hose and it drives fine now". They do start going out around the same time it seems. Dad did brakes in spring and replaced one hose, but this past weekend he replaced the other side as it acted up on him.

DFD536

When I look up collapsing brake lines, it shows that the calliper may stick after applied, I don't see anything about applying itself.. This will actually apply the brakes over a long period of time.. IE I take off on the highway, let the truck coast to be sure brakes are not stuck, do not touch the brakes, and after a little while of driving, the brakes will start to apply. Seems like it must be a booster, or possibly abs problem? unless you know something more specific about the brake line collapse that I don't see? (which is certainly possible)
Thanks for the ideas, keep em coming!

47Dodge

The rubber brake lines going to the wheels allow the fluid with pressure to go to the caliper to push the pads out when applying the brakes. WHen you take your foot off the pedal the pressure relaxs allowing the pads to relax off the rotors.....if the inside layer of the rubber hose is collapsing it holds that fluid under pressure not allowing it to relax and release. It may look brand new on the outside. I really doubt all 4 of these hoses (1 at each wheel ) are having problems at the same time.

I dont know how the new Dodges are as I just got my 2005 but on the old trucks with drum rears there is one rubber line somwhere out back that goes from the main steel line to the rear end area and then steel lines to the wheels. Allows for the suspension to travel up and down. If this collapses then both rears wont act right.

47

rockcrawler304

Jack up the front end and set on jack stands. Apply E-brake and start the truck. Turn the wheel all the way to the right so you can get to the brake hose on the driver side. Have someone slowly apply and release the brake pedal several times as you spin the front tire. Also hold the brake hose and try to feel for pulsating in the line as the brakes are applied.

This can be a poor mans way of "Possibly" detecting an ABS issue. You should NOT feel any pulsating while the brakes are applied.

If no pulsating, I would bleed the front brakes A LOT! get a big bottle (32oz) of brake fluid and run the whole thing through the front calipers, alternating left and right. You may have some junk built up around or behind the pistons.

After the above is done, report back your findings.

rockcrawler304

This can happen due to the brakes already dragging a small amount. The brakes drag and build up heat. If you have any moisture in the fluid, and I am sure you do, the fluid will expand and cause the piston to be pushed out which applies the brakes without you ever touching them.