poor rear braking after Explorer 8.8 disc swap

[Ace of Spades]

My First post on this Forum. Ive been reading, seems to be a lot of talk about RABS. I have a 94 2WD Ranger did the Exp. rear swap for rear Disc. No ABS light problem but terrible brake performance as far as it seems worse with the rear disc. I know the fronts were doing all the work. Even warped the new rotors, got new ones now. Re bled the system re bled the new master. Still weak performance. I looked at the rear rotors. There is hardly any friction or force it seems. The sides don't have a shiny metal look to them. Will try and post a pic. Any way I jacked up the rear. Fired it up, put it in drive. Hit the brakes. There is a very noticeable delay as when the rears stop turning and lock up. Tried it by unplugging the RABS plug and the module fuse. A much better response and the rears lock up much quicker. Test drove it seems much better. Question Is rear ABS a must? Also would a larger bore master cyl be a help? Any Ideas would be great.

 

[chvlfrk]

I've got a 94 with a 00 Explorer 8.8 rearend, mine was direct swap, and brakes work fine.

I've heard of people havin problems, but I never had any issues, and I've done it on 93, 94, & 95 Rangers.

 

[willy]

Abs isnt a must but if you live where it snows it helps i would look into blockage in the break lines try pushing compressed air through them

 

[RangerSVT]

Brake master cylinder is fine, so is RABS. Problem is your proportioning valve needs to be swapped for a 4 wheel disc unit...

SVT

 

[Ace of Spades]

I have no issues with snow just rain here. I took the fuse out of the panel for the RABS module and have been driving it a day. I do notice a big difference. For the better. I will try it in the rain if it rains again soon but will try a few hard sudden stops to see if it locks up bad and spins. For the longest time I noticed the "normal wear" on the rear rotors appeared that the pads were barely making any hard contact as there is not a smooth shiny silver look on the surface of the rotor. I have some pics.

 

[Ace of Spades]

In regards to the proportioning valve, I could not find one. My truck does not have one. I traced the 2 lines directly from the master cylinder. The lines out from the MC go directly the front disc and the other port or fitting go below to the side of the drivers side frame mounted ABS valve then out to the rear axle.

 

[RangerSVT]

Iirc, the abs valve is also the proportioning valve...

SVT

 

[Ace of Spades]

Ok so get one from a Explorer similar to the one I took the rear end from? I think it was a 98

 

[RangerSVT]

Any 96-01 explorer...

SVT

 

[Ace of Spades]

OK one more thought Could it be that the RABS module or valve was not completely with out air in the system or completely bled. Does it need to be actuated or jumped to get the air out of the accumulator?

 

[Napabandit]

I did the explorer swap on my 93 Ranger and due to a delay from a broken neck, completely drained my brake system. I had the same problem until I pumped brake fluid from the rear calipers up to the master cylinder. My RABS was full of air. You can activate it, but I'm poor and didn't want to buy the tool. Now my brakes work like a charm.

 

[Ace of Spades]

Thanks for the info on that swap. Mine sat a few days, fluid drained out too. I wonder or guess I could get a donor harness from the bone-yard and make some sort of a pig tail harness to plug into the unit, maybee find the right terminal, put juice to it, trigger the RABS and do a thorough re bleed of the rears.