1995 e350 ABS module leak?!

Justgosurfin

Active member
I’m assuming this is the ABS module for the rear brakes (no front abs on a 95).

How concerned should I be about how it looks? Seems like there’s a rubber gasket failing or being squeezed out and the forward hose (outlet) seems to be a little leaky. Will tighten and top off today.

If I replace it do I need to have a shop bleed it or is it just the same procedure as a bleeding after a caliper change?

Thanks for any help.




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eblau

Adventurer
Its called the RABS valve, (rear ABS valve or dump valve).... they leak and also the piston that allows it to relieve rear brake pressure can get stuck causing some weird braking problems. Just get a new one and move on, I always bleed that in between doing the rears and the fronts. Never had a problem.
 

Justgosurfin

Active member
Its called the RABS valve, (rear ABS valve or dump valve).... they leak and also the piston that allows it to relieve rear brake pressure can get stuck causing some weird braking problems. Just get a new one and move on, I always bleed that in between doing the rears and the fronts. Never had a problem.
Ahhh now I see the bleed nipple.

Thanks. On the list.


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Justgosurfin

Active member
Its called the RABS valve, (rear ABS valve or dump valve).... they leak and also the piston that allows it to relieve rear brake pressure can get stuck causing some weird braking problems. Just get a new one and move on, I always bleed that in between doing the rears and the fronts. Never had a problem.
And of course no one sticks it anymore.


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Bikersmurf

Expedition Leader
It can be difficult to determine, but can a newer RABS valve be used? I’m not much better off than you with mine being a 12/‘96.

I’ve got a 2001 M/C and Booster in mine. I had to have custom brake lines made to connect it to the RABS. By ‘01 the M/C has a larger bore. I’m happier now with the way the brakes feel.
 

eblau

Adventurer
I bought two of them a couple years ago from NAPA. They were like $150 or so. You could also bypass it entirely and use a newer master like the previous poster said or just learn to modulate the brake pedal so you don't lock the rear wheels up. The valve is really only effective when you dont have any load in the rear.
 

Justgosurfin

Active member
It can be difficult to determine, but can a newer RABS valve be used? I’m not much better off than you with mine being a 12/‘96.

I’ve got a 2001 M/C and Booster in mine. I had to have custom brake lines made to connect it to the RABS. By ‘01 the M/C has a larger bore. I’m happier now with the way the brakes feel.
Interesting. So you feel like you gained some stopping power?


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Bikersmurf

Expedition Leader
Interesting. So you feel like you gained some stopping power?


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More responsive brakes. Less travel to get same force. Once I replaced the vacuum pump a second time... more powerful brakes.

If the rear brakes were out of adjustment... more time before no brakes
 

Justgosurfin

Active member
I bought two of them a couple years ago from NAPA. They were like $150 or so. You could also bypass it entirely and use a newer master like the previous poster said or just learn to modulate the brake pedal so you don't lock the rear wheels up. The valve is really only effective when you dont have any load in the rear.
Thanks. Ended up finding it at oreillys


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Justgosurfin

Active member
More responsive brakes. Less travel to get same force. Once I replaced the vacuum pump a second time... more powerful brakes.

If the rear brakes were out of adjustment... more time before no brakes
Did you take any pics during that swap? Was it pretty plug and play besides the custom line? This would be a long way down my todo list but sounds like a good idea


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Bikersmurf

Expedition Leader
Did you take any pics during that swap? Was it pretty plug and play besides the custom line? This would be a long way down my todo list but sounds like a good idea


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I think there are a couple pictures of the master & booster in my build thread, but none of the swap. The parts look the same on the outside and were direct bolt in with zero mods. The lines just had different sized fittings on the ends.

The only unknown was which line went to the front and which went to the rear. I asked a mechanic I knew, looked at the way it was, and made an educated decision... got it right and they work great. Although having traffic suddenly come to a dead stop when doing 80 mph with a 9k+ rig still wakes you up quickly.
 

Justgosurfin

Active member
Ah man. I commute on I-95 in south Florida a lot and use the van as a work truck quite often. The big vehicle is great for muscling through lane changes when everyone is being space cadets on their phones. But man you said it. Sudden stops aren’t super fun.

So which line ended up going where?


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Justgosurfin

Active member
Got the new rear ABS unit installed without much of an issue but I did have to use vice grips to get the flare nuts loose.

Here was my process:

1. Instructions say to pump the pedal with engine off about 20 times to relieve pressure

2. Disconnect battery ground cable and unplug the ABS unit electrical connector

3. Crack loose but then snug up both flare nuts just enough to stop them from leaking

4. Remove mounting bracket and unit from frame (1/2” socket)

5. Using an impact wrench remove the old unit from the mounting bracket (leave the old unit dangling by the brake lines)

6. Install new unit onto mounting bracket with some blue loctite on the threads

7. Mount new unit and bracket to frame (finagle it in there behind the dangling old unit)

8. Remove rear brake line plug (forward hole) from NEW unit and keep it handy to plug the port on the OLD unit in step 8

9. Remove rear brake line from old unit and install into new unit (plug old hole). Mine took some working to get the threads started but I didn’t lose much fluid

10. Remove supply line (rear line) from old unit and install it into the new unit

11. Connect new ABS electrical connector

12. Bleed brakes in the following order (top up brake fluid throughout the process to prevent emptying reservoir): passenger rear, driver rear, new ABS unit (5/16” on nipple), passenger front, driver front.

Done! Return the old unit for your core charge




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Bikersmurf

Expedition Leader
Ah man. I commute on I-95 in south Florida a lot and use the van as a work truck quite often. The big vehicle is great for muscling through lane changes when everyone is being space cadets on their phones. But man you said it. Sudden stops aren’t super fun.

So which line ended up going where?


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I copied how it was plumbed originally. Closest to the firewall went to the front of the truck, and forward went to the rear of the RABS.
After speaking to a few mechanics and doing as much research as I could, I took an educated guess. I also figured the two M/C would likely be oriented the same... and it worked. :D
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