Brake Fluid Flush and ABS

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Sep 26, 2017
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I recently replaced the two 'front' Rubber Brake Hoses and Pads on my 2002 Ford Ranger.
I may have made the mistake of letting too much fluid drain from one of the lines (Reservoir did NOT go dry).
Haynes Book says, "Warning: if you let air into the system, you will need an expensive tool to fix".
I then flushed the Fluid thru all four Bleeder Screws (2x) using my Speedi-Bleed (Reservoir pressure setup).

The flush went well, but I'd like to get a 'higher' pedal.
Pedal goes down about 15-20% of travel before braking begins / similar to prior working on it.
I feel safe driving it, but could it be better ?

How can I be assured I have NO air in the ABS Modulator ? ? ?

Observation:
The flush consisted of pressurizing the Reservoir and fluid came out all four Bleeder Screws.
When changing the Pads, I compressed the Caliper Piston and fluid went up into the Reservoir.
Either way, the fluid was traveling thru the ABS Modulator.

I always assumed the ABS Modulator was an 'open' system (until needed).

I would prefer not paying a Mechanic to check with his expensive tool (I feel safe driving it).
As an experiment, I could brake while on loose gravel / ice, and any air would expel thru ABS system and I could do another flush.

Just curious what extra precautions / problems people are having after changing Brake Hoses or doing a flush.

I also pulled the Rear Drums and cleaned, inspected, adjusted them.
Thanks for reading and commenting.
 
Last edited:
Also, make sure you bleed from the calliper furthest away from the ABS module first, not the master cylinder (sometimes they are on opposite sides).
 
As long as no air is introduced between the master cylinder and ABS modulator, you should be OK. That happens if the reservoir is dry enough to uncover the ports. I don’t think Ford has a special procedure to bleed the brakes with a bidirectional scan tool(unless it’s a hybrid or electric) unlike GM and Chrysler with Kelsey-Hayes or Delco ABS.

I generally don’t like to push fluid back towards the MC when I reset brake calipers. I like to crack the bleeder and push/reset the piston, then bleed. That way, no dirt enters the ABS modulator.

I'd imagine if you had air in the abs system you'd get an abs light when the car performs it's self checks.
If anything, the brake pedal would be spongy after a bleed has been done due to trapped air in the modulator. Only Toyota/Ford hybrids will throw a C11xx/C12xx code for brake pressure issues. The self-test is there to cycle the solenoids and motor when the car is moving after KOER.
 
ABS blood pressure check. 👩‍⚕️
Brake Bleeder.jpg
 
I bleed brakes on Toyota hybrids in the same manner - use a scan tool(Techstream or a Autel/similar with Toyota-specific software on it) with a Motive bleeder pressurized at 5-10psi. It works well.
AMEN, brother you pointed out the difference between a scan tool and a code reader, nice post
 
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