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-   -   Ford Expedition Brakes (http://www.hotrodders.com/forum/ford-expedition-brakes-162285.html)

Augusto 07-25-2009 08:23 PM

Ford Expedition Brakes
 
well this is not a hot rod but it carries a hot rodder and his family:

my 1997 For Expedition (5.4 engine, 4x4, air suspension) is a great suv, it only has 50.000 miles on the clock and is like new, very comfortable and I use it only for traveling.

the problem is that this thing has the worst brakes I ever had in a vehicle, including that bicycle that I used to brake rubbing my right shoe against the front tire.

I have installed new ford pads in all 4 corners, replaced the fluid, checked the calipers, etc, etc, but the brakes can just not stop this behemont.

bear in mind that here we live in the mountains and the brakes take some punishment, going downhill at any speed over 30 mph I must shift into 2 or the brakes will overheat and quit working.

lats week I had a close call, this typical idiot made a sudden maneuver in front of me, going downhill at probably 45 mph or so, and I slammed the brake pedal with both my feet and pushed as hard as I could but the car barely slowed down, the tires didn't lock (of course the abs must have worked) but they should have at least lay some black stripes, nothing, I almost rear-ended the other car, I made a dangerous maneuver to avoid him since the brakes just didn't stop the car.

I also own a 99 explorer that on the other hand has excellent brakes, it does lock-up the tires even though the abs makes them chirp or whatever, you know that typical abs grab and hold sequence.

in the expedition I have 3.30 diff ratio and in the explorer 4.11, but this shouldn't make a braking difference (does help the explorer slow down when going downhill though, it's not necessary to down-shift from D most of the time)

Do you guys know of a cure for this problem? or know of a factory problem on this model?

thanks.

Augusto.

327NUT 07-26-2009 12:42 AM

I've got an '02 F-250 Powerstoke diesel and was less than satisfied with the brakes. I did some research on an RV forum and found that most of the guys who did a lot of towing upgraded to Carbon Ceramic pads. You can find them on the internet, Ebay etc.

They work better but I still don't have the good feel that I would like, must just be the way Ford's brakes work. Also if your ABS is working properly you shouldn't have any "black stripes" on the street. I personally don't like ABS, don't like the feel of the pedal pushing back at you. By the way did you turn the rotors when you changed pads? I know its an added cost but it sure helps the pads break in properly.

Augusto 07-26-2009 09:24 AM

nope I didn't turn the rotors, maybe I should had but I'm sure it will not improve to the level they should perform, actually I feel this brakes are quite dangerous.

My explorer does lay rubber when I smash the brakes, the tires do stop, the ABS releases them and applies again, they make the braking noise and the truck stops, the expedition brakes like a granny, well slows down because braking.. really braking is not doing.

I had tougth of installing a master cylinder of a smaller diameter, will this alter the ABS performance or make it act weird?

is there any posibility of the ABS unit interfering with my braking?

there are no trouble codes stored, and I can feel it working, it does work on muddy roads, helps steer while braking on the mud, I'm an experienced mechanic and I know it's working, but I have this tougth that it may be interfering, I have never seen or heard of a problem with the abs interfering braking but with ford who knows?

thanks.

Augusto.

T-bucket23 07-26-2009 09:34 AM

We have had no issues on those getting them to stop.Are the pads free to move in the caliper. If not this will give you a hard pedal but no stopping power. I would pull it back apart and see if the pads all look like they are getting good contact. We seldom change pads without changing rotors anymore. The new rotors seem to seat the new pads properly with them getting glazed/hardened.
Has it always been bad or just since you did the brakes.

Are you the original owner, if not I would make sure you have the correct master and make sure no lines are pinched.

Augusto 07-26-2009 10:41 AM

I bougth this car from the US Embassy here with only 35.000 miles on it and was the ambassador's personal so it was in like new condition, was always serviced at the Ford dealer so I believe everything is OEM and correct, looks like the master cylinder is the original unit.

there are no pinched lines and the caliper pistons do move, the old pads had even wear patterns.

it always had bad braking power, maybe this is why they sold it???

but seems like it has worsened latelly, funny thing is that the brakes work fine at city speeds but on the road they are scary to say the least.

seems like the car is too heavy and was not designed to be used on mountain roads, but then it is rated for towing something like a couple of tons or so...??? it should brake fine, shouldn't it?

I deglazed the rotors with #80 sandpaper when I changed the pads, getting new rotors here would cost me a lot of money, oem parts here are very pricey, I installed original ford pads tough, they had both ford and motorcraft but I opted for the more expensive ford parts, I wonder if I did right??

what do you think?

T-bucket23 07-26-2009 11:16 AM

We have a lot of issues witht the Ford SUV's but braking is not one of them. The e-brakes on the rear disk models are horrible to say the least but we have not had any brake efficiency issues. Usually poor braking is due to binding pads or calipers. We sand blast all pad contact areas on the calipers and or caliper mounts depending on the brakes style. Check all slides to make sure they are free and use high temp silicone grease on all sliding surfaces when assembling.
We use a lot of oem parts lately, if we dont use OEM we usually use Wagner thermo quiets.

Augusto 07-27-2009 07:21 PM

thanks a lot for helping, I'll take them calipers apart and double check the pistons, I haven't removed the pistons but saw them moving, maybe they don't go out freely or all the way, good oportunity to replace the fluid also.

thanks again.

Augusto.

Augusto 02-29-2012 03:47 PM

Still Same Problem
 
here I go again,

the expedition just got new original ford pads up front and motorcraft in the rear, the 4 discs were turned, checked everything, the master is the original 1.25 in dia., everything is fine, I made test with the ABS fuse out and the only difference is that on dirty tarmac a tire or two do lock up, but the same problem, it takes forever to slow down.

I tested the vaccum on the booster side of valve and the engine pulls 18 inches of vaccum, which is normal for all engines over here at 6.600 feet of altitude, no engine makes more than 18 inches and the brakes work fine, I repeated the same test in my explorer and got the same results, onl difference is the explorer brakes real well and the expedition scares the living crap out of me.

since everything is fine I'm believing this is a problem of a wrong size parts for this huge suv at the andes mountains, something radical needs to be done.

bigger brakes is out of the question due to very high cost of brakes and wheels and tires that must albe be changed.

the only thing that comes to my mind is replacing the vaccum boster for a hydraulic, hydroboost unit from a C30 or F350 trucks.

I believe this will improve the braking, what do you guys think?

john-john 03-02-2012 07:24 AM

diagnostic tip
 
pull the ABS relay and try the brakes again.

a bad, out of adjustment, or incorrectly installed abs sensor can trip the ABS.

it happened on my dad's '97 Econoline after the ford dealership did the brake service. it activated the front ABS and since the front brakes are responsible for 80%+ of the vehilce braking it made the brakes miserable.

check the owners manual - sometimes the hazard lights/4-way flashers disable the ABS. it's an easy test and disabling ABS is a nearly necessary feature on snow and ice.

Augusto 03-02-2012 08:26 AM

already tried disabling the ABS but did not improve braking, only change was a rear tire locking up.

john-john 03-02-2012 08:29 AM

Quote:

Originally Posted by Augusto
already tried disabling the ABS but did not improve braking, only change was a rear tire locking up.

you should be able to lock a front wheel. i'd start looking for air in the lines or a closed proportioning/safety valve.

Augusto 03-02-2012 08:32 AM

went to this hill yesterday and coming downhill I made several panic stops, the first one it slow down fairly well but took too long to stop, made a second one and it took soooo long, sure crash would of be if it was a real panic brake, third one I had to use both feet and almost bent the steering wheel, it took even longer to stop, carefully went back to the shop that's about half mile down the road and measured the temperature of the discs, pads and calipers, an average reading was 310 deg farenheit for the rear brakes and 290 deg for the fronts, this means that the pads are being applied and the bias is right, but maybe not enough clamping force? what would be a temperature reading after three very hard brakings?

Augusto 03-02-2012 08:58 AM

there's no air, I have bled 'em several times, the fluid comes out briskly, don't seem like there's any restriction in the lines.

checked the calipers again and the pistons move freely.

I'm believing Ford screwed up, this truck is so big for it's brakes on mountain roads, well when I've been down to the coast and on sea level flat roads is about the same, this rules out the theory I had about being 18 inches of vaccuum too little for the booster to work, besides all vehicles here have good brakes but mine. :pain:

Irelands child 03-02-2012 12:26 PM

Agusto - that sounds like you have a recurring problem, based on the original date of this thread.

First of all, this Expedition is an F150 with a different skin which means that the brakes should be good enough. One question though - since you said that this was a US Embassy vehicle, does it have any armor plating on it, increasing the actual weight by a lot?

Then, I do have to say that even as loyal a Ford owner as I am - they come equipped with some of the poorest calipers, soft rotors (low end of the hardness scale for these parts) and crappy pads. I know that you are having to pay ridiculous prices for parts, but I would at least change out the pads to Hawk LTS (there are others as good). Then when the time is right, the rotors. Of course, chilled iron, cross drilling and/or slotted are best, but I've been using Brembo or Centric OEM replacement and am very happy with their stopping power and life.

Just for a some discussion - these from my F350 had 36,000 miles and were 2 years old. http://i70.photobucket.com/albums/i8.../LFRotor21.jpg. Their replacements now have ~40,000 miles and look like new. Our now sold Escape - 22,000 miles - OEM brakes were totally gone. Replaced with the Hawk/Brmbo combo - looked good at 90,000 when sold.

Dave W

75gmck25 03-02-2012 07:35 PM

Unless the vehicle is much heavier than standard, the brakes should work fine. I got rid of my 2000 Expedition with 167k miles on it, and I think I only put brakes pads on it 2 or 3 times.

I used to run the truck heavily loaded on vacation. It was a longer stop with a little more pedal pressure when loaded with six passengers, luggage, car top carrier, etc., but it was never as scary as you describe. I was using OEM rotors and Wagner brake pads (don't remember if they were ceramic). For most mountain driving I just clicked the overdrive off, but also dropped to 2nd if it was a really long downhill run and there were curves.

Bruce


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