Ford Rabs Valve Diagram Wiring
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Discussion Starter · #1 ·
Hey I have a 1994 f250 ext cab long bed diesel. I want to get rid of the anti lock brakes on the truck. what sensor can i disconect to make the antilock stop working. The tranny is a E40D. so i wanna get rid of the anti lock brakes without hurtign the tranny. Please dont tell me that its a stupid idea and everythgin or ridicual me about it. its just the back brakes on the truck they hit once then antilock kicks in and they dont act like they do anythign afterwards. Also im used to not havign anti lock brakes and much would rather have normal brakes not antilock.
thaks,
jimmy
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Bypass the RABs valve on the frame....... remove and save the valve though they are really expensive and someone will buy it.
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What about just unplugging the harness off the RABS module? Won't that disable the valves in it and make it behave like a straight piece of brake line?
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The brakes are acctually anti skid not antilock. Antiock brakes unlock and reapply so fast you cant tell it. Anti skid unlock and stay that way. The truck speeds up as the rear brakes quit . This will scare the hell out of anyone, you think you are going to shove you foot through the floor. LOLOLOL
If you were to disconnect them you might swap ends the first time the brakes lock-up.
FWB
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Discussion Starter · #5 ·
so what is the best thing you guys reccomend do? i really need to get this truck to stop better then what it is now.
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I think I'm gonna go and bypass it hydraulically, then at first opportunity convert to hydroboost - I now have a Chevy hydroboost with a rod that's 1" longer than it should be, but that's actually good cause I really don't like the brake pedal so low, so really I only need the hoses... which will more than likely come from a Chevy truck again, seeing how that's about the only hydroboosted vehicle I can find at the junkyard
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I just pull the fuse on mine and then remove the warning light bulb from the dash. I have done this on several trucks and it works every time so far. Ford RABS is dangerous IMO.
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Well last night I disconnected the harness from the RABS module, and it felt like the pedal is going to the floor, you know, as if the solenoid goes wide open and when I get on the pedal the fluid has to first fill that piston-accumulator-thingie and then start building up pressure... Does the RABS need some key-on power to keep that solenoid shut so I can build up pressure like normally?
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My brake & ABS lights are on all the time (the ABS light goes off very briefly right after I start, then comes right back on). I'd prefer to correct the cause of the problem, but so far haven't been able to. So, I disconnected the wiring from the RABS control module. The brake & ABS lights are now off, and the brakes perform just fine. BTW: this is my first post. I've been lurking for a few weeks now. Great site!
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Congrats on your first post!
My brake & ABS lights are on all the time (the ABS light goes off very briefly right after I start, then comes right back on). I'd prefer to correct the cause of the problem, but so far haven't been able to. So, I disconnected the wiring from the RABS control module. The brake & ABS lights are now off, and the brakes perform just fine. BTW: this is my first post. I've been lurking for a few weeks now. Great site!
You will find alot of great advice here from people that are more than willing to help. I too have the same issue with my truck and working with a few ideas regarding the RABS valve. Ie.. removing springs.. disconnecting.. bypassing. I dont know what the brakes were like when this truck was new but its less than acceptable now. Im getting used to it but had a friend drive it yesterday and forgot to tell him about the brakes and his face turned white the first time he had to stop quick.. lol.. wouldnt be a good rental truck..
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My brake & ABS lights are on all the time (the ABS light goes off very briefly right after I start, then comes right back on). I'd prefer to correct the cause of the problem, but so far haven't been able to. So, I disconnected the wiring from the RABS control module. The brake & ABS lights are now off, and the brakes perform just fine. BTW: this is my first post. I've been lurking for a few weeks now. Great site!
We've been discussing that topic over at FTE for a while now, and someone brought up an excellent point - RABS-equipped trucks do not have a proportioning valve, they rely on the RABS to back off the line pressure when the rear wheels can't handle it and start locking up. If you bypass or disable the RABS you're now supplying the rear brakes with full line pressure all the time, meaning they will lock up so easy it's scary. Non-RABS trucks tackle the issue with a proportioning valve that reduce the pressure to the rear brakes, and often a load-sensor on the rear axle to drop the pressure even more when there's little to no weight in the bed. So the correct way elliminate the RABS would be to either install a proportioning valve for a similar GVWR non-ABS truck (requires modification to the front lines as well), or install an aftermarket brake-bias valve between the master cylinder and the rear axle.
I actually ran in that issue with my old Chevy truck, it was a shortbed stepside truck that even with full tank and me and a passenger was still under 4000 lbs, yet the brakes were powered by a 1-ton hydroboost system (both booster and master cylinder), and to top it off my tires were mismatched front to back as well (32x10.5 fronts, 33x12.5 rears) - I used a Willwood manual brake-bias valve to sort out this mess, it took me a while to get it right but in the end the decel was so good it could throw you in the windshield and still not lock up any tires.
So keep that in mind when you go about shutting off the RABS, unless you do something to reduce the line pressure when you run empty your truck will be very much unsafe on low-traction surfaces like wet pavement or snow.
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Im going with the stiffer springs therory... will let you know the outcome once i dial it in ..
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Hey, just pull the fuse and try it. If you don't like the way it feels, put the fuse back in. Like I said, I have done this to several trucks and the brakes are good. My rears are not lockup prone at all.
The RABS valve is bound to have some sort of default proportioning setting for if the system goes down. I doubt it is "wide open" as you say or else I would have locked up the rears big time the other morning when a deer jumped out in front of me.
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yep, my ABS light is on too... in a 94.. i'm not sure if it's just a sensor or if the ABS is actually disabled. sure feels like it is. but like y'all are saying the "ABS" in these trucks is kind of screwy anyway. havent checked the fuse or anything yet, i just got used to the ABS dummy light.
i'm not messing anything up am i?
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Jstrauss, you drive a SRW truck, correct? These ain't as prone to wheel lockup as dually trucks are, tis when you have 4 across the rear with little to no weight on them when things get real scary real quick.
Dieseldirt, are you sure you have no air in your brake lines? It will mess with the ABS big time, so check the fuse and if it's good then try bleeding your brakes before condemning the electronics. As to messing up something - your yellow warning light shows something's already messed up with the RABS, whether tis someone pulled the fuse to disable it, or disconnected harness to the HCV on the frame rail, or tis a VSS going out in the rear axle...
Source: https://www.thedieselstop.com/threads/how-to-get-rid-of-anti-lock-brakes-on-94-ford.212489/
Posted by: morepeople54.blogspot.com