Weak Brakes

[bbressler]

Got a quick question that I think I know the answer to, just wanting to verify....

Are the brakes and power steering run off the same pump?

As you may recall, I had my power steering hose explode again and had to run the pump dry for a few hours. While the power steering is working fine, I am having a hard time stopping. It feels like I'm pulling a big trailer with no brakes on it, when I come to a stop it just keeps going. The pedal isn't spongy or anything, it just feels like it's lost it's "clamping force"...

Thanks.

 

[Zookie400]

does your truck have hydro boost? i thought all obs' were vaccuum, unless someone chaged it over aftermarket?

 

[trackspeeder]

Only the F SuperDuty had the hydroboost brakes.

 

[bbressler]

I checked the vacuum line going into my brake booster, it sucks ok...when I unhooked the line, I heard a sucking sound, so I think it's holding pressure OK..

so....are ya'll saying that the hydroboost system is the one that uses the PS pump? Any ideas on my weak braking condition?

 

[milspark1]

I had the same problem when I replaced my rear brakes. I had to go back the next day and readjust my rear pads. You might can check that or maybe try bleeding your brakes to make sure there is no air in the line somehow.

 

[Crumm]

Are the brakes and power steering run off the same pump?

No. The brakes are run off the vacuum pump and the steering is run off the Power Steering pump.

Sounds like your vacuum pump may be getting weak.

 

[Zookie400]

is the pedal firm or spongy?

 

[bbressler]

pedal feels just like it always does...wouldn't call it firm, but not really spongy either...

It seems like I've always been able to keep pushing through the pedal Previously, the harder I pushed, the quicker the stop, but it seems like there was always some more to press. Now, I can get to the bottom of the pedal, it just doesn't stop like it used to.

Another note -- I know in the 130K miles I've had the truck I've not done anything to the rear brakes....could they be finally wearing down enough where they don't have the stop they used to?

I hope it's not the vac pump...that'll be my third one of those, too!

 

[Zookie400]

if the vac pump stops pumping, the pedal will be rock solid.

its possible there is a little air in the lines, i assume you checked the res. fluid level.

also check for leaks while someone is pressing (or pumping if the pedal reaches the floor) sometimes the smallest leak is enough to screw your braking power but not let fluid hit your driveway.

if the brakes were down to metal, you would hear it, and they actually would start to get VERY grippy at 10mph and below.

check your wheel bearings, front and rear. if a set of wheel bearings (1 hub) gets some play, the wheel will ride out on an angle and push the piston on the caliper back in; when you step on the brake it will use the piston travel of the caliper to straighten the wheel out, rather than build pressure on the rotor (needed for stoping!). it can also happen on rears as well, even with drum brakes.

thats all i have off the top of my head for now. hope you find something quick and easy!

 

[DOC-MX]

check your wheel bearings, front and rear. if a set of wheel bearings (1 hub) gets some play, the wheel will ride out on an angle and push the piston on the caliper back in; when you step on the brake it will use the piston travel of the caliper to straighten the wheel out, rather than build pressure on the rotor (needed for stoping!). it can also happen on rears as well, even with drum brakes.

This happened to me one time, everybody thougth that was the master cylinder, but was a bad front wheel bearing.