Help me please woman owner of 99 dodge cummins 24 valve 4x4 emergency brake light and abs keep cumn

[Kassidygee]

I get pressure on my brake pedal. But it locks up when i get close to stopping completely so i learned to slow sooner and really softly to the light to stop to avoid them locking up.

 

[KATOOM]

Which tires lock up? All of them or just the rear or just the front?

 

[NIsaacs]

Re- did the brakes

Did you do all four or just the front? Do you need to add brake fluid at all? If the rear brakes get any brake fluid or axle oil on them they are prone to lock up, the front locking up is rare. The ABS light can be tough to find.

 

[Wayne M.]

Hi and welcome to the TDR!
Please make a signature for yourself and your truck, so we have some reference.
Now could you please start from scratch and just tell us about what the brakes are doing? Or not doing?

 

[GAmes]

No one has asked if the speedometer works normally when the ABS light is illuminated. Also, the factory service manual (FSM) for mine gives a good troubleshooting procedure. Does one for year ???? include one? Do you have an FSM? Have you checked the transmission fluid level?

 

[fest3er]

If the '99's RW ABS is anything like the '98's, you should expect to lose almost all braking when the RW ABS kicks in; it's an undocumented defect.

As to why it happens, I suspect that the CAB (Controller, Antilock Brake) detects a sudden drop in rear wheel speed while braking, and engasges the RWAL brake system which also dumps most of the front braking. Why the sudden change? Your rear shocks could be bad and you're braking on a rough road, or the signal from the rear sensor to the CAB drops out, or you have a speedometer correcting device (TruSpeed, Abbott) installed and it isn't working quite correctly. Each looks like a sudden drop in rear wheel speed while braking.

Braking returns once the vehicle speed reaches around 2-5 MPH because that's the lowest speed the CAB can reliably detect.

But when this happens, you *should* notice the speedo dropping to zero.

Only other reason I can think of is there could be an intermittent break in the cabling between the CAB and the rear wheel speed sensor.

 

[Mike B.]

Te 99s were first year to come standard equipped with 4W anti lock brakes.

Both of my 99s only have rear wheel anti lock.

 

[Joe Mc]

Best money I spent on my truck when I got it in May of 01 was a Factory Service Manual. Very helpful. If you don't have one go to
https://www.genosgarage.com/category/dodgeram-factory-service-manuals

 

[Road Dog]

RE: your brakes,
I had the awful rear wheel ABS on my '98. When the ABS thinks the rear wheels are locked and activates then the brake pressure is released on all 4 wheels. I rolled past a few stop signs when the ABS kicked in.

When the ebrake and ABS lights are on then it's an indication that the ABS has a fault. There is a sensor on the top of the rear diff that detects the spinning diff and uses that to detect locked rear wheels. It also provides a signal for the speedometer so if the speedo is erratic or the speed drops to zero at low speeds then the sensor or the connector is the issue. There are a few causes. Sometimes the wiring is damaged. Sometimes the connection is corroded and needs cleaning. Sometimes the sensor isn't fully seated in the hole in the diff. Sometimes the senor is broken and needs to be replaced.

 

[petersonj]

because I was loosing braking power and they would lock up on me.

I experience loss of braking power they would lock up on me when id brake and jerk the truck id let off the brake and have to press it again to come to a full stop.

I get pressure on my brake pedal. But it locks up when i get close to stopping completely so i learned to slow sooner and really softly to the light to stop to avoid them locking up.

I have been following this thread, but I am having a difficult time understanding exactly what you are experiencing, mainly because you say, "I was loosing braking power and they would lock up on me" or similar statements. Loosing braking power and lock up are two opposite events. So, for clarification I am going to make some assumptions:

* You are driving the truck about 40 mph on a dry flat pavement.
* You step on the brake pedal to slow your vehicle and the vehicle begins slowing.
* You notice that the brakes are not slowing the vehicle as quickly as you think they should.
* You push on the brake pedal more firmly and some tires lock up and skid on the pavement.

Let us know what is true and is not true.

You know exactly what all the conditions are when this event happens because you are there. It will be most helpful for us to help you if you can detail exactly what you are experiencing. Be very specific, leave nothing for us to guess about

- John

 

[fest3er]

* You are driving the truck about 40 mph on a dry flat pavement.
* You step on the brake pedal to slow your vehicle and the vehicle begins slowing.
* You notice that the brakes are not slowing the vehicle as quickly as you think they should.
* You push on the brake pedal more firmly and some tires lock up and skid on the pavement.

More like:

• She is driving at some speed, then applies the brakes.
• The vehicle is slowing as expected, then most of the braking 'cuts out' without warning.
• At some slower speed, full braking 'returns' with a vengeance.

This is exactly what happens with the faulty, sub-standard RWAL brake system designed into at least some '98s. If the brakes are applied and the CAB notes (thinks) that the rear wheel speed suddenly changes, it will engage ABS which reduces *all* braking by at least 50%, not just rear braking. The apparent sudden drop in rear wheel speed can be induced by either the wheels actually stopping/skidding or the CAB losing the signal.

When ABS is activated due to signal loss, so much braking is lost that one naturally pushes the brake pedal to the floor. Should the CAB restore normal braking before the vehicle is (nearly) stopped, the result is sudden, maximal braking.

The only workaround is to make the CAB think the truck's in 4WD all the time.

This is really the only complaint I've ever had about my '98.

 

[petersonj]

@fest3er, thank you for the explanation. Now I understand how the symptoms and the actual cause do match. Maybe @Kassidygee will confirm what you have described.

- John