To start with this thread is purely for research purposes as I don't intend on removing ABS on either of my trucks at this moment, or possibly ever. I've just been digging through some older threads and trying to learn more about removing the Kelsey Hayes 4 wheel ABS system from '95+ GMT400s. I found this very informative post from DRAGGIN95 in another thread:
So basically it looks like you need a combination/proportioning valve and some new lines. Here's where my questions begin. So instead of a junkyard '88-'94 proportioning valve and front lines, let's say you wanted to use an aftermarket adjustable combination/proportioning valve. Would something like this Wilwood unit be appropriate? If so are the fittings the correct size? (Looks like the Wilwood has 3/8"-24 inverted flare)
https://www.wilwood.com/MasterCylinders/MasterCylinderProd?itemno=260-11179
Also I've seen others mention using a residual pressure valve on the rear line for the drums, Wilwood has a 10lb one that they recommend for this purpose. Is this necessary?
https://www.wilwood.com/MasterCylinders/MasterCylinderProd?itemno=260-13707
Any info is appreciated, my knowledge of this stuff is very limited.
I have done this several times, on 88-94 2wd truck like mentioned you remove the ABS control module and rear abs valve, be sure to keep the proportioning valve though you need it to keep proper brake bias from the front and rear brakes. Anyway run a new piece of line from the rear brake line junction on the frame just below the firewall to the proportioning valve and that's it. For 95+ originally there are 2 independant lines running to each front brake caliper that run directly to the ABS unit, there are 2 way's to deal with this, either unhook the both front lines at the abs unit and install a tee, or what I do is go the salvage yard and buy the front brake lines and proportioning valve off of a 88-94 the front lines on a 88-94 tee together originally so with this method there are no other tee's needed, I can get it all locally for $10. The rear on the 95+ still only uses 1 brake line that runs directly to the abs unit, it can be unhooked and hand rebent to hook up to the 88-94 proportioning valve, or you can just buy a new piece and run it from the junction on the frame under the firewall to the prop. valve. It's not difficult to do at all. Also one interesting note when the power and other plug's are unhooked from the abs unit on the 95+ the abs in dash light does not come on, even though you would think it should.
So basically it looks like you need a combination/proportioning valve and some new lines. Here's where my questions begin. So instead of a junkyard '88-'94 proportioning valve and front lines, let's say you wanted to use an aftermarket adjustable combination/proportioning valve. Would something like this Wilwood unit be appropriate? If so are the fittings the correct size? (Looks like the Wilwood has 3/8"-24 inverted flare)
https://www.wilwood.com/MasterCylinders/MasterCylinderProd?itemno=260-11179
Also I've seen others mention using a residual pressure valve on the rear line for the drums, Wilwood has a 10lb one that they recommend for this purpose. Is this necessary?
https://www.wilwood.com/MasterCylinders/MasterCylinderProd?itemno=260-13707
Any info is appreciated, my knowledge of this stuff is very limited.