identifying an ABS equipped car or truck

Over the years I've owned a few cars with ABS and have looked under the hoods of a few others with ABS....different car companies have different ways of building this system into their vehicles. My old G20 had a "box" up near the radiator that all the brake lines were routed to/through. I've seen some Cavaliers with brake boosters equipped with circuit cards/electronic controls that I'm assuming were the ABS controls "piggy-backed" onto an older system. And my folks have 2 Tauruses, one is a '99 with a sticker on the driver's window that says ABS equipped which their newer '02 or '03 does NOT have.

Do ALL ABS equipped cars have some kind of warning light that comes on when the car is first started...like nearly all instrument panel lights do for just a few seconds until the engine starts? Is there any other nearly fool-proof way to tell whether or not a car a dealer says is ABS equipped, really is?

As far as I know, the ABS dash light is a positive indicator. Otherwise, check the owner's manual. Or do a panic stop. ;-)

David

On most,just look at the mastercylinder. The ABS will have a larger unit with extra lines and electrical connections. Non ABS, well it looks like a normal master cylinder.

That rear ABS was the dumbest regulation our gov't came up with. ABS working,front wheels lock up, can't steer. From experience.

iceracer wrote: On most,just look at the mastercylinder. The ABS will have a larger unit with extra lines and electrical connections. Non ABS, well it looks like a normal master cylinder. That rear ABS was the dumbest regulation our gov't came up with. ABS working,front wheels lock up, can't steer. From experience.

MAN DON'T GET ME STARTED ON THIS ONE! I have had several ford econoline work vans with rear only abs and they are dangerous. The work van carrys nearly all of its wieght on the rear wheels, alowing the the fronts to lock up very very easily. The front wheels lock up and the abs system seems to think that the truck is stopped, so the rear abs does absolutly nothing. much worse than no abs in this particular application.

My current work truck is a freightliner sprinter with 4 channel abs & 4 wheel disks. It stops on snow better than some early abs cars!

Yeah, I didn't mention it earlier, but my first experience with ABS was with a '94 Ranger and it's rear-only ABS...I never could tell if it was really doing anything so I can't give it a "thumbs up" or a "thumbs down". Newer Rangers have 4 wheel ABS and I have considered buying a new or late model Ranger, I just think at this point I need something with better fuel mileage.

One of the main reasons why I brought this topic up is that I often see cars advertised as having ABS in classified ads that I don't believe were ABS equipped from the factory.

My G20 didn't have an unusual master cylinder, but instead had that "accumulator-type" thingee? up near the radiator that I assumed had brake lines running into it, though it could have also been something strange to do with the fuel injection?

iceracer wrote: On most,just look at the mastercylinder. The ABS will have a larger unit with extra lines and electrical connections.

False. There have only been a few slip control systems over the years that required a MC that was externally distinguishable.

iceracer wrote: That rear ABS was the dumbest regulation our gov't came up with. ABS working,front wheels lock up, can't steer. From experience.

Rear-Wheel Anti-Lock was designed to keep the back end behind the front end, plain and simple. It was implemented on vehicles which have wide variation between LLVW and GVW. Here's how it works: Feds and/or manufacturers have stopping distance requirements for LLVW and GVW. Rear brakes have to be big enough to stop the vehicle at GVW, but that makes them oversized for LLVW, and makes the base brake balance rear-biased. Rear-biased means that the rears lock before the fronts, and that's a key point. In a truck operating at LLVW, the rear brake effectiveness is saturated well before the fronts. Without some kind of balance modifier (a height-sensing prop valve, a load-sensing prop valve, or an anti-lock system), the rear brakes will lock at a vehicle deceleration that is lower than what it takes to lock the fronts. As a completely pulled-from-ass example, let's say that the rears will lock at 0.4g while the fronts won't lock until 0.9g. In this example, any deceleration greater than 0.4g will lock the rears. And what do we do when we hear a skidding tire? We reduce brake pedal force, to unlock that brake and avoid damaging our tire. But that means that we can't pull greater than 0.4g decel with this vehicle, even though the front brakes wouldn't lock up until 0.9g. Now, with a rear-wheel anti-lock system in place, we don't lock rear brakes anymore when the vehicle is at LLVW, and we have usable deceleration (surface-dependent, of course), all the way up to the example 0.9g limit of the front brakes.

What's not to like?

Interesting... So when did trucks and SUVs start having real 4 wheel ABS systems? I'd like one in the future tow rig.

Depending on the manufacturer, trucks and SUVs started getting 4 wheel ABS in the mid '90s. I would say pretty much any truck or SUV built WITHIN the last 9 or 10 years for sale in the U.S. has 4 wheel ABS. I don't recall if there was an actual Federal reg that required ABS in these vehicles by a certain date or not. By and large, GM "seemed" to switch to 4 wheel ABS quicker than Ford or Chrysler...the most popular vehicles (at Ford, the Explorer and F-series) got it first, followed by the cheaper trucks.

angry corvair, the place where you put the brake fluid is usually on the master cylinder which is connected or integrated with a hydraulic control unit, so it is still easy to identify vs a non abs master cyl.

The only time I've actually seen a ABS control unit attached to the master cylinder itself was on a Lincoln Mk VII. On the cars I've looked at, it seems far more common to find the ABS unit bolted to the inner fenders or some other spot a distance away from the master cylinder.

Here's two master cylinders for the same year, make, and model, only one is for ABS and one isn't. Can you guess which one's which?

Rear-Wheel Anti-Lock was designed to keep the back end behind the front end, plain and simple.

Works well for that. It's saved my bacon in my Ranger at least once. Driving along on a rainy day, somebody pulled out in front of me, jammed on brakes, rear end starts to come around (90% of the weight of the truck is on the front tires at this point), ABS kicks in, truck corrects attitude and I stop a couple feet from a terrified soccer mom.

I might have been driving too fast for conditions, granted, but I think it did what it was supposed to do, and for that day, I was glad to have it.

MSM....I'm beginning to come to the conclusion that many/most domestic brand cars have the contol unit for ABS on the master cylinder. At least the few GM and Ford vehicles I've seen were like that. The G20 I had had the control unit near the front of the car, I don't remember if it was attached to the inner fender or not. I wish all the domestics had done it like the non-domestics did, that is, put ABS in every model or make it standard on the highest trim levels so that yahoos couldn't say that a base model Crapola Limited has ABS....when at best it was optional....then you have to determine from what you can or can't see under the hood if the salesperson is an ignorant SOB.