1998 Ranger 4wd,49,ooo original miles. My brake pedal gives a single pulse sometimes just before i come to a stop. Brake system is in overall good shape with new front brakes, lines all around, good rear brakes. My mechanic told me the pulse is from the ABS pre-maturly kicking in and will eventually be a expensive fix. Anyone have an idea what I can expect as far as future brake performence and what kind of parts/expense may be involved? BTW, no warning lights are going on.

 

is the speedo acting up? does the abs light come on? any clicking from under the dash when you brake?

 

I have heard that some brake pads can cause the abs to act up......was the truck fine before the new work? I also have heard sometimes the abs acting up becasue it was not bledd correctly?

 

A breif history of the truck. Got it in April for my son who is stationed 600 miles away. Changed all fluids and was aware the brakes were bad from the pulsing/vibration when breaking. Had all new front brakes/lines installrd, back were ok. I drove it everyday for a few weeks to make sure all's well then drove it down to my son. Was visiting him several weeks ago and drove it a little and noticed the slight single pulse in the pedal just before a complete stop and my son said " oh yea, been doin that a little". He makes a suprise visit up here last week for a few days and as fate would have it blew a rear brake line in our driveway the night before departure. Able to have my mech fix it next morning and asked to check out the pulse and thats when he said about the fix. No lights or strange speedo, didnt notice a clicking under dash. Will have the truck back here in Nov to do whatever.

 

I did a little googling fo ryou and this is what i found. take it all with a grain of salt.

it looks like your abs wheel senosr could be acting up. each front tire has one. they are not integrated into the hub so it looks like replacing them is a simple 15 minute fix. the parts appears to be about $100 each. rockauto.com if you can figure out out how to get the abs codes read it will proably tell you what wheel( maybe both) it is.........you do have a abs/vss sensor in the rear differential these do act up but the symptoms are a little different. that part is $20 and a 10 minutes fix. maybe you can do a search and see if these sensors can get dirt on them and act up.keep us posted

 

Thanx, Sounds like an easy logical first stepto see if i can just clean the sensors.maybe a can of compressed air with a straw.Gotta start somewhere, now all I need is the truck to make its way back here. Even replacing both(3?) sensors isn't gonna break the bank. Weird how the abs light isn't coming on, maybe not bad enough yet.

 

VSS is only one of thee sensors of ABS (this is 3S/3M system by ATE), so inspect front WSS, sometimes WSS reads speed the wrong way if there is a bearing play, so inspect and ajust front bearings

 

Had the same happen to my '99. The ABS would activate w/o warning during low speed stops under dry weather conditions. This was getting dangerous. Stopping distances increased big time when they should not have.

You can feel the front wheel bearings for play, but removing and cleaning the front wheel speed sensors is the best form of attack.
I just lazy and pulled the 50amp fuse that handles the ABS motor. Yeah, the ABS light stays on, but the truck now stops on a dime. I have no more scares of running through store fronts or hitting cars in front of me at traffic lights.

 

Hmmm, interesting cure. Pull the fuse and back to old school brakes! Cheap and easy...Will be thinkin on that one !

 

Honestly, save your $.. it won't be the sensors.. I have the same problem which started after I installed new pads/rotors. I compressed the caliper with a C-clamp which forced fluid back toward the master cyl and messed up the ABS. After exhaustive research, I think the only way to fix is to get to the dealer and they can bleed the ABS with their scan tool. Or, do what I did and unplug the damn ABS g/l

 

yeah, there is ATE program that opens modulating valves to bleed pump.

but to be sure, try to pull codes first

 

Whats ATE? Anyway back in April when my mech did the front brakes didnt he have to bleed them, so why/how would bleeding be dealer specific with their scan tool? And when you say pull up the codes you're meaning ABS specifically? I guess I can get one of those homer Actron ABS scanners for $100 which is probably what a dealer would charge me anyway. Problem is that scanner is only compatable with 2 outa 4 of my vehicles, whatever. Think I'll just try to clean the sensors ($free) and if they still act up pull the fuse( thats really ok?), poured enuff money in that Ranger already.Besides, I suspect from what I've been reading on this forum the 4x pulsating hub system may be an issue down the road! This truck is really, really clean inside/outside, not a scratch, no rust. Looks kool with big tires,mags, lighted visor and stepside. Son loves it just hope it don't turn into a bigger moneypit.

 

ATE - company, that makes brake system for Ford, Volvo, Pegeot, Mercedes Benz and other.

They have tool, that work via OBD-II ore directly k-line from control unit (no k-line on US OBD-II connector). They may read, clean codes, do valve/pump actuation and program units. In Europe we have really good diagnostic tool - Bosch KTS (450/500/550 and other). It is expencive tool, but it works well with many cars and I can test ABS with it. Ford VCM tool have ATE subrogram included and dealers may do all the right way.

Belive me, no moror company that make all the systems and tools, brake systems are made by ATE, Bosch, Wabco, Bendix and Brembo. Air suspention - Wabco and Bendix/Bosch/Knorr (really Knorr makes air ore hydraulic systems, Bosch makes electronics - they sell products with different brands on different markets).

There are other companies, that play electronic brake game, for example - Haldex. They offere ABS, EBS, TEBS for light and heavy trucks.

Japanese systems are clones of European systems, Toyota, Honda and othey do not use european systems, like US companies, they try to make propriate systems with other names.

Really we call ABS - Anty Blok Systeme - like in Germany, not lock preventing system!

Well, what to advice - get more sufisticated OBD-II scanner and if you'll get ABS codes active ore stored, lease post them here. may be the problem is different.

If WSS codes exist the best way to test them - analolog VOM, ~ current. I use to jack wheels and measure WSS voltage for drop, air gap, damaged tone rings, bad wiring, bearing play. relly the best, but longer way to find problem.

 

FWIW, I don't think any affordable scanner would be able to find the codes the dealer will find with his pricey tool. I have a fairly expensive brake scanner (as well as a regular scanner) and no codes come up, so I really wouldn't recommend buying one just for this. No ABS light = no codes for us to see..If you unplug any of the front sensors, your brakes will work like normal brakes. The only thing you will notice is the ABS light on all the time..

 

Ok- so i now have the Ranger with me. dealing with the crappy 4x vacume system too but thats another story. Back to the ABS doing a hard pulse at stops. I noticed in the owners manual there are actually 3 seperate 4whl ABS fuses. One 10 inside by door panel and two ,30 & 50 under the hood in the power dist. box. Took the fast and easy way first and pulled the interior 10 amp which got rid of the pulse but the speedo stopped working. Put fuse back in and speedo worked, pulse back. Before I pull any of the others , which one? Does the 50 overide/disconnect the other two? Is there some kind of mix and match? Yank all three?