I drove from Chicago to Indiana and visit my parents over the holiday.  I had been in Indiana about 2 days, driving down the street coming to one of the worst intersections in town and pushed on the brakes and it was like pushing on a solid rock.

I'd gotten both the ABS and the brake light for about 24 hours before that but I looked on the forums and no one seemed to be very concerned about it. So I didn't think much about it figure I'd fix it when I got home.

While I was stopping and the brakes weren't responding I felt the brakes come back the pedal went down like it should and I was able to stop the truck. 

Can the ABS cause a problem like this? It seems that I have no problems as long as the ABS and brake lights are on but whenever they go off I can feel the pulsation in one of the brakes the funny stuff that you feel when your ABS sensor goes out. The truck is a 2001 Dodge ram diesel club cab long bed.

Thank you.. Gary

I can only guess as to what to look at. Check all fours for any leaks, after a run make sure none of the wheels near the center are excessively hot from a stuck on brake caliper. Check fluid level. Other than that I cannot remember if the brakes on a second gen has vacuum assist brakes. If so, check the vacuum lines and clamps for leaks or deterioration and cracks.

 

Hoping others will jump in with more than I can offer. Be careful out there.....

No vacuum assist on hydroboost. The power steering pump provides the assist. Check you power steering fluid level. Have you checked for trouble codes?

This is my second Dodge Diesel and I have never had to do anything to the brakes except change pads. I have changed injection pumps, recabled the batteries, changed the alternator and never noticed there was no brake booster.

The power steering pump never made a sound, but the fluid is low. I filled it and will take it easy till I am sure that still solves the problem.

I still have to figure out why my brake and abs lights are on.

Thank you for the help.

Well it seems I was mistaken, filling the power steering unit did not fix the problem. The problem is coming from the ABS and It only happens when the fault light on the dash goes out. I had read that I can completely disconnect the ABS by unplugging the unit behind the glove box. Can anyone tell me which connector it is that I unplug?

Thank you, Gary Moore

I wouldnt discount the power steering yet.

 

Also not sure I'd go by the indicator lights on the dash. 

 

Jack up front tires ensure power steering is full. Turn wheel slowly with cap off power steering resivor.

This will purge air. 

 

Check brake resivor. Check all 4 corners for leaks.

While front is off ground turn tire and notice if wheel bearings are crunchy and dragging.

The bearing goes out and gets hot enough to melt the abs sensor.

 

If no leaks and everything seems good. Bleed all four corners. Starting at banjo fittings on calipers then go to bleeders screws. Would best with a helper but can be done alone.

 

With abs light on something is wierd. Leaks, low fluid, air, master cylinder itself, sensors. Since yours seems mechanical I'd say it's not the front abs sensor. 

 

If it's cold there it could be seals,master cylinder and calipers 2winters ago we dropped to -15s and my brake system pretty much went **** up and said I'm done. Calipers leaked master pretty much everything with a rubber seal gave up.

 

 

 

All good points above, I would also check alternator for ac noise and clean all grounds. Could be something damaged in abs module making it not function properly. I would also flush power steering fluid and might as well flush break fluid. Make sure all air is out of both systems. See what happens. 

You can also rebuild your own calipers pretty cheap and easy, same goes for hydro boost if needed, power steering pump I'd get new if possible and needed. 

Pedal being hard tells me something isn't letting fluid through. There is a little screen on pressure power steering side, when you undo the hose you can unscrew the fitting to pump, there will be a spring in there that may jump out and little piston with screen on it. iirc

On 12/26/2019 at 7:09 PM, Gary L Moore said:

Can the ABS cause a problem like this?

 

Yes you need to change all the unit bearing in the front with new sensors and the problem will be solved. Note of warning you could replace the sensors alone but if the tone rings are damaged in the hubs it will not fix the problem. What it is that the sensor is reading on wheel at ZERO speed and you touch the pedal the ABS will back pump the pedal and prevent braking because it thinks one wheel is already locked up tight and trying to get the speed back. 

 

Been there done this... Just remember I've got 3 sets of sensors and never fixed it till I replace both front unit bearings then the lights went out and problem solved. 

Ok. I have not checked the wheel bearings yet. I am sorry to hear this, but ya gotta do what ya gotta do. I sure cannot drive it safely like this.

Bearing will be fine most likely but the tone ring will have spun free and broke its spot welds. 

Can't he just unplug the ABS module to get him home safely?

1 hour ago, kzimmer said:

Can't he just unplug the ABS module to get him home safely?

No. Speedometer will be gone. You can unplug a front sensor to trip a code and disable the ABS.

On 12/27/2019 at 10:10 AM, Evan said:

I wouldnt discount the power steering yet.

 

Also not sure I'd go by the indicator lights on the dash. 

 

Jack up front tires ensure power steering is full. Turn wheel slowly with cap off power steering resivor.

This will purge air. 

 

Check brake resivor. Check all 4 corners for leaks.

While front is off ground turn tire and notice if wheel bearings are crunchy and dragging.

The bearing goes out and gets hot enough to melt the abs sensor.

 

If no leaks and everything seems good. Bleed all four corners. Starting at banjo fittings on calipers then go to bleeders screws. Would best with a helper but can be done alone.

 

With abs light on something is wierd. Leaks, low fluid, air, master cylinder itself, sensors. Since yours seems mechanical I'd say it's not the front abs sensor. 

 

If it's cold there it could be seals,master cylinder and calipers 2winters ago we dropped to -15s and my brake system pretty much went **** up and said I'm done. Calipers leaked master pretty much everything with a rubber seal gave up.

  

T

Quote

 

 

Thank you for the responses. I need to do something, the computer keeps flicking the trouble light on and off, so my brakes go on and off. I ordered new tires and had to drive it to the tire store. I still have to get it to the mechanic when he calls back. I would do it myself, but my garage is busting at the seams..  Thank  you for the reply.

 

 

 

On 12/28/2019 at 10:47 AM, Mopar1973Man said:

Bearing will be fine most likely but the tone ring will have spun free and broke its spot welds. 

 

And that tone ring is welded on the back of the bearing?

8 minutes ago, Gary L Moore said:

 

And that tone ring is welded on the back of the bearing?

 

INSIDE the bearing and un-repairable... You have to replace the unit bearing.

Is there a way to confirm that is the problem, can it be seen? I am going to have them replaced anyway. Is it possible to see while the hubs are still mounted that the ring has separated? thank you for all your help MM.

Go to Dodge Dealer and spend the money for labor for a dealer tech to pull out DRBIII tool and measure the front axle speeds while driving. There is no cheap tools for the public Snap-on is expensive tool as well. Even my Innova tool won't do ABS on these trucks.  

Yeah, I understand how that goes. Ok.. I appreciate the help. I am going to look for the wheel bearings and hubs now. Cannot get the Timkens locally, will have to order. Gary

Edited December 30, 20195 yr by Gary L Moore
added information

Don't bother with Timken... Waste of money. I've been getting 180k to 200k+ miles from SKF unit bearing from NAPA.

 

Edited December 30, 20195 yr by Mopar1973Man

On 12/30/2019 at 8:50 AM, Gary L Moore said:

Is there a way to confirm that is the problem, can it be seen? I am going to have them replaced anyway. Is it possible to see while the hubs are still mounted that the ring has separated? thank you for all your help MM.

You can take sensor out and see the ring with teeth. Maybe stick a flat screw driver in the hole and rotate the hub. If you can hold ring in one place while spinning the hub you need new bearings. If they are original they have plastic races and could lock up at some point if they get hot. Most of them didn't come with enough grease, some people put extra grease through sensor hole, some put a grease zirk in and grease them that way with sensor out of the hole so extra pressure/grease won't blow seals out. Don't overgresse need some air space in there too. Look at the sensor when you pull it out make sure it's not damaged by the teeth, if it is don't bother putting a new sensor in, bearings are wore and have enough play to hit the sensor.

I've been fighting ABS brake light come  and go for a few years, ended up being sensor in the rear end.

I have Timken bearings that I got through RockAuto.

Won't work... Need a DRBIII tool. I've tried the prying the tone ring. Didn't slip in my case. But my right hub would not register speed below 40 MPH. So the ABS assumes the wheel is locked. 

 

Even with 3 sets of sensors would not register speed. Had to replace both bearings to fix.

Edited January 2, 20205 yr by Mopar1973Man