Hi all,

First time post here on the boards.

Probably asked and answered a thousand times, and I've searched the threads and found about a dozen different answers, but feel free to flame away anyway (and then help out if you can).

New to me, 2000 D2 with soft, almost squishy brakes. Not all the way to the floor, and decent stopping power, but definitely much less travel and more pressure on second pump. Recently had all four wheels off and checked pads: all four wheels have new pads, and none of the wheel cylinders show any signs of leaks. Although I didn't mic the rotors, there doesn't appear to be any grooving or a defined edge that would indicate excessive wear. Also, no signs of any leaks at the MC, and it's not eating fluid.

Did two bleeds: one following the RAVE process, including sequence, and another using the traditional "pump and hold" method. I did manage to get some air out of the system, especially at the first (front right) wheel I bled. Maybe a slight improvement, but still not what I'd expect/hope for. Also inspected lines for any bulging or damage and none visible, even when applying pedal.

I've heard of internal seal failures at the MC that allows blow-by, but no resulting leaks. Is this my next step? New MC, bench-bled, then a complete re-bleed of the system? I didn't see anything in the RAVE regarding any bleeding specific to the ABS, but I know some vehicles do have a bleed valve on the modulator as well.

Thanks,

 

You'll need something like a hawkeye or a lynx diagnostic tool to bleed the ABS. Best bet would be to take the truck to a shop with a testbook to bleed the ABS for you.

 

when i bought mine i had the soft peddle too, and the owner before me took it to a shop for a new MC, multiple bleeds and could never get the feel any firmer.

so i got a Nanocom and ran the ABS pump while pushing the brakes firmly a few times and then bleed the brakes and its much better, but still could use some work. but iv not messed with it sins i got it working a lot better. maybe a little later i go threw and do another brake bleed for the abs pump and the lines.

 

You can run the ABS pump yourself by shifting to low range and engaging the Downhill Decent Control. At low speed hit the HDC button and let the vehicle slow down, bleed the old fashioned way, repeat as needed.

There is also a way to directly power the ABS pump with a jumper cable but I like the HDC method better even though it is a second choice for use when a "textbook" or other computer is not available to activate the pump.

 

Master cylinder.

 

Thanks all. New MC ordered. Will bench bleed it, and install. Can I bleed the system without running the ABS pump, or am I p#@&ing in the wind?

 

Can you elaborate more on the HDC method?

As I understand it, I drop the truck in low, at a slow speed, hit HDC and let the truck slow down with no application of pedal, just let the ABS pump do it's thing. Then, pull truck into garage and bleed brakes as normal.

When you say "repeat as needed", do you mean until all air is out of the system, and do the whole process, including the HDC every time?

Thanks.

 

Probably easier to buy a scan tool that can operate and read the ABS system. These trucks are notorious for brake related warning lights on the dash, that scan tool will pay for itself in a year.

 

You've got the HDC method right. The only need to repeat is if the pedal is not as firm as it should be. You'll know. Then yes, activate the ABS pump again.

Just like the cooling system you have to get every bubble of air out.

Plus its a good excuse to exercise your T-case shifter and HDC.