ABS - a cost effective upgrade?

[hq_]

Over ten years ago, after a couple of close calls and eventually rear-ending someone because of the notoriously crappy ABS system, I disabled it on my Ty. It's the original factory system without recall upgrades - Metro-Auto (GM in Finland) doesn't honor recalls, not even safety ones, and filing a complaint to GM headquarters didn't help.

So, I'm on my own.

I'm finally about to upgrade the brakes with an LS1 setup and I'd like to re-install ABS to my truck at the same time. The problem is, there's no way in h*ll I'm going to put up with similar problems that caused the accident and numerous close calls in the 90's.

Does anyone know if there's another, more modern GM ABS controller that could be adapted to Ty without having to fabricate almost everything from scratch? The wheel sensors are still there (and will be if needed, with LS1 brakes), all wiring is intact and brake lines haven't been modified.

I'm prepared to keep my ABS delete, but I'd feel slightly more comfortable if ABS was there when my wife and teenage kids drive the truck; their ability to modulate braking is limited and knowing how hard replacement cladding is to come by, I'd rather not have them crash it by plowing into something, brakes locked.

Any ideas? I'm comfortable with working with electronic and mechanical devices and adapting a non-original system isn't an impossible task for me, but I don't want to re-invent the wheel if someone has already done an upgrade like this before.

 

[bonesdmz]

Re: ABS - a cost effective upgrade?

Subscribed. This is a very good idea.

I would start with searching for some schematics of modern GM (of Ford, it doesn't matter) ABS units. If they could work without ECU, then we are happy. You'll only need to adapt ABS sensor signals.

 

[hq_]

Re: ABS - a cost effective upgrade?

Thanks for the info, Quadrajet, but I have some bad news for you: mine's a '92 with sensors on all wheels. Otherwise it worked semi-decently, but when you hit a bump when braking hard / treshold braking, ABS kicked in and virtually all braking power was lost. Not good; I get shivers thinking about the two times I ran through an intersection at 40-50mph, standing on the brakes, ABS happily blasting away and preventing me from stopping. And of course the Alfa Romeo 156 that was more or less a write-off after I parked my Ty in its trunk. Fortunately back in those days I could get all replacement cladding directly from GM.

I'd imagine the main things about upgrading the ABS system will be wiring (wheel sensors) and communication between the ECU and ABS controller. Finding a car/truck with a similar / the same ECU and more modern ABS would be a good starting point; there's a good chance they'll be able to talk to each other without major wiring or protocol issues. I'm not very familiar with GM wheel sensors but if I've understood correctly, they're very simple on-off units that'll just send the speed pulse to ABS controller.

Availability of virtually any kind of salvage parts from US-market vehicles is poor around here. Otherwise I probably would have already acquired a bunch of GM ABS controllers and tried them out with Typhoon ECU and wiring. Boneyards ask hundreds of euros (multiply that by 1.38 for $) for parts like these so any experiments get very expensive very quickly.

Bonesdmz: if you manage to figure something out about this, please let me know. Knowing which unit even looks like it could work would be excellent; I think the pump itself won't be a problem but electronics that control it are.

Btw., '97 Chevy Suburban I sold last year had amazingly decent ABS system even though the brakes itself sucked. Being able to upgrade the electronics of my Ty to that level would suffice for me nicely.

 

[hq_]

Re: ABS - a cost effective upgrade?

It's not "bad news" to me. I'm satisfied with the way my 92 systems work. If you don't like the way your 92 system behaves, so be it. You're not alone in this regard. Lots of peeps remove it. And just how fast do you drive if you're "sliding through intersections at 40-50" with an activated ABS? If this was in inclimate weather (snow) I understand. If it was dry, sheese I won't ride with you.

Occasionally I may drive like a jackass, but bear in mind that intersections with traffic lights in 44mph (70km/h) zones aren't exactly uncommon around here. All it takes for situation I described to happen is 10mph over the limit, bad timing and Typhoon's notoriously unpredictable ABS. We're talking about situations where average, working brakes would've easily been enough to bring a car/truck to a halt before the traffic lights.

Can we skip preaching the ethics of traffic behavior, please? I've had a FIA international racing license and raced (in sanctioned events, mainly touring cars) since the 80's so I might have a clue when brakes are causing real safety issues, instead of me causing them myself.

Good luck in your research regarding a retrofit ABS system. Just so you know, the SyTy ABS is a stand-alone system There is NO interface between the BPMV and the engine ECM or "ECU" as you refer to it as. The wheel sensors output a square wave signal.

Thanks. If you're sure about this, I'll take your word for it. I was just wondering how it relates to ABS diagnostics that are performed shorting the A and H pins on ALDL, ie. does the ABS controller have direct access to ABS warning light on dashboard? In some vehicles ECU and/or the electronics in dashboard itself control all the lights and data has to be transmitted from ABS controller to either of them.

I've mainly worked on Nissan (Skyline/GT-R) and Mercedes ABS systems lately and I really don't know the inner workings of GM ABS. At least not yet.

 

[Beavis]

Re: ABS - a cost effective upgrade?

I vote to just pull it out. I did and haven't missed it one bit. With the All Wheel Drive, you are lees likely to have them lock up under normal conditions anyways. Plus I give a little extra room in front of me anyways because front ends aren't as easy to come by as they used to be.

 

[SY2455]

Re: ABS - a cost effective upgrade?

Only thing I'm sure about is that no matter how I try, every time I respond to a peep on here with a low post count (n00b) I get a ration of shit from them. I've got to stop trying. To answer your question, I don't have a clue about SyTy. I've never owned one, and never worked on them. I have no idea how any of the systems work, or are integrated. I'm one of the most Ignorant people on here. I just make stuff up because it sounds good. I'm only 12 years old. I just troll around looking for noobs that can't tell that I have no idea what I'm talking about and make stuff up. Don't trust anything I say. It's all BS.

Have a nice day. Go mess with your nissans.

Now Dave.........:rotf::rotf::rotf::rotf:, I know it must be hard..........:rotf::rotf::rotf:. You need to cut the nOOb some slack, After all he has this thing for 10 years and just now found this site :rotf::rotf::rotf:. JK, I needed a good laugh after a really bad day yestraday Thank You for giving me 1.

 

[Quickstop [UK]]

Re: ABS - a cost effective upgrade?

I wondered about this as well. Do you have Vauxhall or Opel in Finland?

Rather than specifically wanting a GM unit, why not consider any other unit with 3 sensors? Volkswagen/Saab must have similar systems? You would need to adapt the solid lines (easy with some braid/adaptors) and then make sure the sensors were outputting the same signal. You could probably achieve this by installing new sensors. It will need some research.

I don't think anyone has done an ABS replacement so you would be charting new territory., at least as far as SyTy goes. I'd be interested. ABS has come a long way I would imagine since 1992.

 

[hq_]

Re: ABS - a cost effective upgrade?

I don't think anyone has done an ABS replacement so you would be charting new territory., at least as far as SyTy goes. I'd be interested. ABS has come a long way I would imagine since 1992.

Thanks for the reminder about GM Europe cars, Opels are very common and I completely forgot about their corporate relationship with GMC. Saab has been owned by GM for quite a few years too so something usefult might come up.

I'd prefer retaining the ALDL diagnostics option if that's possible, which is why I'm interested in whether the ABS controller connects to ALDL socket directly or through ECU. GM ALDL scanners won't most likely work if the controller is from a OBD2 / post-OBD1 vehicle but even "blink"-based diags are far more useful than nothing when something goes wrong.

This may well be the first time anyone attempts something like this, but I'm a bit surprised if no-one has researched the subject earlier. Development in ABS systems has been huge during last two decades and the original system is only marginally more modern than any computer or electronic device is by today's standards. Then again, it isn't by far the first time I've fabricated something "new" for the truck, back in the 90's few of the upgrades that are now considered common were available.

As a sidenote, it's somewhat hilarious or even sad that some posters - who apparently have little or no relevant knowledge of technical details concerned - drag the conversation to off-topic, which serves absolutely no point other than their personal amusement. Kind of funny, no-one in SyTy circles has ever called me a "n00b" before, not even when I first started posting to the original syty.org mailing list almost 15 years ago. Back in '97 when I volunteered to be one of the country contacts (wow, the ancient list is still online at http://www.syty.org/old/representatives.html) everyone had quite a bit more common courtesy and signal-to-noise -ratio was far better. Maybe the world and perceived attitudes have just changed.

Ok. Off the soapbox and back to "charting new territory". Thanks for the tips, I'll have to get my hands on GM white papers and see if I find out something about the controllers' communication protocols.

 

[bonesdmz]

Re: ABS - a cost effective upgrade?

http://www.aa1car.com/library/abs_list.htm
Check this out.

 

[hq_]

Re: ABS - a cost effective upgrade?

A quick update, I dug out the service manual I had stored in basement years ago.

The ABS controller is connected directly to all sensors, ALDL pin H (CKT696 diagnostic request) and antilock warning light. It doesn't seem to communicate with ECU or other electronic controllers at all so it's more or less a standalone unit. This will make replacing it much easier, without having to worry about communication protocols.

In theory, a more modern ABS controller + pump that is designed to work with either three or four 900ohm-2kohm wheel sensors would only need modifying brake lines and electrical connections to work. Controllers that require connection to ECM, BCM, CAN bus or the like are out of the question, of course, but I don't have a clear idea how common that is nowadays.

'93+ trucks with vehicle speed sensor instead of four wheel sensors may be slightly more difficult, depending on which controller is compatible with stock VSS. Having to swap the VSS may result in losing the speedo so that isn't a realistic option.

In any case this swap is starting to look quite a bit easier and more straightforward than I originally thought. Now I'll just have to figure out what would be a suitable donor car, one that has as modern and performance-oriented ABS as possible. My wife's Audi RS6 has a fantastic ABS system and finding a way to adapt something like that would be ideal, but it just may be "too" modern as far as retrofitting the electronics is concerned.

 

[hq_]

Re: ABS - a cost effective upgrade?

http://www.aa1car.com/library/abs_list.htm
Check this out.

A good find. Thanks!

 

[gdiwicker]

Re: ABS - a cost effective upgrade?

Anyone figured this out yet? I just got the bad news that my EBCM is bad and I have to either yank the ABS, find another crappy replacement, or get creative.

 

[hq_]

Re: ABS - a cost effective upgrade?

Anyone figured this out yet? I just got the bad news that my EBCM is bad and I have to either yank the ABS, find another crappy replacement, or get creative.

Doing research on it at the moment. It seems that later model standalone units that have their own controller would be the best replacements - finding one from an AWD vehicle with somewhat similar weight distribution and brake balance would be ideal. Many recent ones need a connection to ECU for traction control, ESP and other features which will make retrofitting difficult. Ones that only need +12V, wheel sensors and trigger from the brake light switch are most promising - the downside is that many of them are old and/or from 2WD vehicles.

There aren't that many different ABS pumps around but the vehicle-specific control unit will make all the difference in how it'll work in practise.

 

[gdiwicker]

Re: ABS - a cost effective upgrade?

What about a Suburu control unit?

 

[bonesdmz]

Re: ABS - a cost effective upgrade?

We should also check Bosch ABS units from AWD BMW E34's. They are old enough, so there possibly won't be excessive CAN etc. connections. But its still BMW unit, so it should work flawlessly.