And here comes the back end around the front end. The #1 thing ABS did was keep the rear end IN-LINE rather than stepping out while allowing you to use the rest of the heavily loaded front wheel's stopping power. Unloaded pickups benefited the most. It's something I was reminded of years ago stopping hard in an old school van as the locked up rear started to step out on me as I had gotten used too ABS keeping me in-line.
The next question is what kind of an up-fitter would take the liability and remove the safety features on a vehicle like ABS?
I have had two different close calls, one potentially deadly when ABS system malfunctioned. One awd Toyota previa and one on my 98 suburban. Both vehicles getting up there in age. You could argue it is the owners responsibility to maintain the ABS system. I agree they work as intended if properly maintained, but I see trying to maintain these 25 year old systems as a losing battle. And when ABS malfunctions, it can be incredibly dangerous. But above all else, it is NOT HARD to brake safety without ABS. It's simple, keep safe distances, understand road conditions, and pay attention. I am also the only one that drives my suburban.
And on the Toyota Previa (350k miles by the way), I pulled the ABS fuse the day I almost got killed by that crap, which was about 8 years ago. Has been a pleasure to drive since. Completely rebuilt brakes (Except ABS fuse still out) front and rear last spring and it stops on a dime.
On Mobility modified vehicles: Even with reduced effort braking and reduced or zero effort steering the ABS system stays. This includes hand throttle/brake controls. Additionally a high current electric powered hydraulic pump is installed to keep the power steering working in case of engine stall/failure. Hydroboost systems by design also have power brakes available from the backup pump.
If you are worried about engine stall then an electric backup pump system may be right for you. It's cost installed is likely more than your vehicle is worth with a full tank of fuel. Just saying you have options.
I am not necessarily worried about engine stall, just pointing out that those guys ragging on safety of manual brakes are overlooking the safety issue inherent in hydro boost. Let's face it, engine stall at speed is a real possibility with a 20 plus year old pmd controlled rig.
The removal of the proportioning valve ... This is becoming a safety hazard even on a race track. You are limiting your front brakes to the ability of the rear brakes. Loaded under some conditions your stopping distance has increased while the rear lock up risk is way higher. Stopping sideways before your increased braking distance plows you into something sideways isn't cool.
The suburban I had was all front brake from the factory. Horrible.
With prop valve removed, the difference in line sizes between front and rear, and difference in caliper piston compared to wheel cylinder seem to result in a pretty well balanced system. I can lock them up from 45-50 and she skids to a hault in a very well mannered nature.
I swear, If you guys could drive my rig, you wouldn't be so hard up against this idea of ABS delete or prop valve delete.
All this work to gut a reliable braking system and I bet you still have an automatic transmission.
I have an automatic in the suburban at present yes, but I have an NV4500 out of donor 6.5 truck that will probably go in. I recently picked up a fourth 6.5 (a crew cab, manual) with bad motor. So I am debating which one becomes the simple beast and which one keeps all the comforts.
If simplicity is the cornerstone to all your mods, I would think a manual swap would take precedence over everything else.
I guess call me crazy, but I always thought these had a good brake system. I really dont care how the pedal feels as long as it stops good, and it definitely does that, can lock them up on dry pavement were it not for the ABS.
Yeah, my brakes aren't bad at all. The soft pedal feel doesn't bother me too much, it's more that I got to thinking if hydroboost offers 4x assist and my pedal feels pretty much effortless, then shoot, I could probably handle manual brakes, especially if optimized with some pedal pivot modification, MC bore size change etc.
Ive pulled Numerous trailers without brakes (either inop or never equipped with from new, heres looking at you farm header trailers) and so im putting alot of faith in the trucks brakes, and they do the job great.
ABS is up in the engine bay, dry and warm. unlike the crap location of the GMT800, down in the salt brine. PS cooler to keep from cooking out the hydroboost seals and hoses, unlike the diesel GMT800 which never had a cooler.
My 98 does not have PS cooler. When I resealed the ps pump and replaced some leaky lines I noticed my 96 parts truck had one. I almost swapped it over, but did not. Wish I had because after that, I had some bad tire wear (alignment shop nocked out factory tangs to allow full alignment adjustments, but didn't snug up the upper control bolts enough) the camber crept in slow enough that I had some bad wear on the new tires before I noticed. Anyway, with that camber in and bad wear, I noticed my power steering pump couldn't keep up well in parking lot type driving. Noticed it in the brakes too. Cooked the fluid.
I have got some new front end components going in before I put these new tires on. New power steering pump in hand that will go in when I engine swap soon. Definitely be adding a ps cooler in line at that point.
Most all of my high miled 6.5Ls are still rocking original hydroboost and steering components, including the 95 with 453K on it. cant say the same about my 06 Duramax, lack of cooler has cooked about everything PS fluid touches.
