Bleeding ABS on OBD-1 Suburban

[Tinker]

I suspect I have air in the ABS unit on my 94 Suburban. Is there a way to bleed the unit without a scan tool? Hoping for some of the same jumper wire magic as with the lift pump rather than taking it to the local shop. I've not been able to find anything in web-land or even on this forum.

 

[ak diesel driver]

find some snow or wet grass to slide the tires on to cycle the ABS then bleed it again.

 

[Tinker]

Thanks @ak diesel driver , I'll give that a try.

 

[smokymtn65]

IN our case red clay or grass .. snow... well might be a while!

 

[Will L.]

Snow???
Grass???
Are you guys making up words again?

 

[Tinker]

Got it done on a gravel road nearby. Still mushy, so I've got some more troubleshooting to do.

 

[Will L.]

It can take a few times doing it like that. I found waiting a few hours between times helped.
The computer really is the best method.

 

[Tinker]

It can take a few times doing it like that. I found waiting a few hours between times helped.
The computer really is the best method.

I'm glad you said that. I went out later to move the truck and the brakes were much firmer this time. I think I'll bleed the wheels again this weekend and see where I stand. Thanks @Will L.

 

[Will L.]

@ak diesel driver is the one for the credit-I just added 2 cents to his solution.

 

[THEFERMANATOR]

92-94 units also have bleeders at the abs unit you have to bleed.

 

[FellowTraveler]

I seem to remember that you start the bleed at the farthest bleeder working your way to the nearest bleeder...

 

[Tinker]

92-94 units also have bleeders at the abs unit you have to bleed.

I thought I had read that somewhere and I see two bleeder screws on the unit. But I haven't found any procedures for this, i.e. do you simply loosen-press on the brake-tighten as you do at the wheels? Or do you need to bleed at the ABS with a scan tool/command unit?

 

[THEFERMANATOR]

You bleed the abs bleeders just like at the wheels, but I believe you need to also rebleed the abs bleeders after actuating the abs unit.

 

[Tinker]

I'll give that a try. Thanks!