No abs, no abs light. Help!!!

[Chris01cummins]

Hey guys can someone please help me. I had to emergency stop twice now and all the truck did was lock up the rear tires and the front did nothing. Rear abs does not work but the light does not come on to tell me there's a problem. The light does work when you turn the key on, then goes out after a couple of seconds. I'm not sure if my truck is supposed to have 4 wheel abs or not but I found the abs wires cut at the hubs. Any help would be great. Thanks

[Mopar1973Man]

First off. I would request that all brakes be inspected and the entire system bleed out with fresh fluid. Make sure the front calipers are not bound up. Then check there rears for any broken springs or issues. Rusting drums can cause the lockup you talk about you might look.

 

Is your speedometer functional? Is it showing speed properly? 

[Chris01cummins]

Yes my speedo does work.

[Mopar1973Man]

41 minutes ago, Chris01cummins said:

Yes my speedo does work.

 

Smoothly?

 

Like when my ABS gave up. The front sensor would show ZERO till 30 MPH and the jump up. This is a tone ring issue in my case. Being I'm going to assume its RWAL (Rear Wheel Anti-Lock). This is the only speed sensor there is.

[Chris01cummins]

Yea, no problems with that. Also when I hit the brake pedal, it kicks back...

[Mopar1973Man]

Can you do me a favor and verify what system we are working with. Do you have a module in the driver side corner with an electric pump? 

 

 

Rear wheel anti lock doesn't have this but two solenoids controlling brake fluid. Then back by the rear axle is a dump solenoid. This dumps pressure preventing lock up. Which typically feel like the pedal sinking. 

 

Kick back would be Full ABS system which typically if a front sensor is bad or tone ring it will kick back or back pump the pedal making it nearly impossible to push down more. 

[Chris01cummins]

I dont think I have that.

[Mopar1973Man]

Nope, you do have the RWAL system. 

 

So the rear speed sensor is important but you said the speedometer is working correctly and smooth. On the ABS system, the only thing it could be is either one of solenoids is stuck or debris in the system.

 

The only thing I could think of since there is no ABS light I would say its either hydraulic or mechanical issue. 

[Chris01cummins]

Ok. I took notice earlier that someone change the front and rear brake lines. The front lines are about half the original size. I know this because they left the old one running across the front cross member. The back still has the original load adjusting lever for the rear brakes.

[Mopar1973Man]

24 minutes ago, Chris01cummins said:

The back still has the original load adjusting lever for the rear brakes.

 

Is it still hooked up? Or.. Is the arm disconnected and wired up in position?

[Chris01cummins]

Its connected. 

[Mopar1973Man]

Now I'm scratching my head for sure. Ther rear lever if it hooked up should reduce the amount of braking force on the rear axle if still hooked up normally. You having issues of locking up. The only thing I can say is inspect the drums for rust of hardware issues. 

[IBMobile]

May be the previous owner replaced the rear brake wheel cylinders with the larger GM type for added braking power.. 

[Chris01cummins]

6 hours ago, IBMobile said:

May be the previous owner replaced the rear brake wheel cylinders with the larger GM type for added braking power.. 

 

It was an old farm truck. 

 

7 hours ago, Mopar1973Man said:

Now I'm scratching my head for sure. Ther rear lever if it hooked up should reduce the amount of braking force on the rear axle if still hooked up normally. You having issues of locking up. The only thing I can say is inspect the drums for rust of hardware issues. 

 

Yea me too. That's why I thought I would ask because I cant figure it out.

[Chris01cummins]

I just really dont want my family to get hurt because of this. Its are only vehicle tho. When it locks, that's it you along for the right. It's like I'm on ice. The front dont do anything. If I brake normal, stops just fine.

Edited January 28, 2019 by Chris01cummins

[Mopar1973Man]

Some thing to try is pull the fuse for the ABS. This should trip the light and disable the ABS system. Worth a try.  

 

If it still locking then it's a hardware issue. Not an ABS issue.

[Chris01cummins]

1 hour ago, Mopar1973Man said:

Some thing to try is pull the fuse for the ABS. This should trip the light and disable the ABS system. Worth a try.  

 

If it still locking then it's a hardware issue. Not an ABS issue.

Ok I'll try that.