powner

Guys - my lexus IS250 2006 (brakes were checked by mechanic just fine 6 months ago) but somehow the car just behaves funny in the snow. Yesterday as it has happened last winter too, we had some snow in the northeast and I was braking on maybe 1 inch snow pile-up on the road (no black ice). I was going about 10 mph and hit the brakes softly just before I got to my driveway and I could feel the ABS come on but the car would not stop easily. I'm surprised the car initiated ABS at such a low speed/soft brake and even after it came on, the car took its time to come to a stop. My 20yr old sedan with regular brakes would perform much better

I've been told I have bad rims and probably need to change in the future but don't think that should have anything to do with braking. Right? What could be the issue here? What should I have my mechanic test out or has there been any recall with this model and ABS in the past?

Thanks

UnderCover

Abs will kick on if your wheels are starting to lock, it's because you're on snow it's totally normal. I would get better tires for the winter if you're constantly sliding, there's no ABS recalls for this call AFAIK

powner

Just got two new tires that costco installed in the rear. He said my front two tires have about 30% life on them

Rezno

iTrader: (1)

It is normal for your brakes to lock on snow and ice. To prevent this, be very light on both pedals and get winter tires.

Retroplay

IMO, the ABS is way too sensitive. I have brand new ExtremeContacts on my IS and the IS still kicks in far too much based on my many years experience driving in the winters. Yes, the ExtremeContacts are HPAS and not truly winter tires but they are highly rated for winter driving. I have had no problems getting stuck with them, just stopping. I have had the IS for only a month now, but I am learning how to deal with it. Just start braking further back, let off, roll a little then brake again until you have no momentum left. That seems to help. Once the ABS kicks on, if you keep applying pressure to brake, you are going to keep sliding.

My mother had a Chevy Cavalier that was like this, too. Almost killed me when it drove me right out into a busy intersection because it slid just a little and the ABS would not let me stop. That was just on some rain-wet road, not even snow. Just note that stopping you quicker is not the purpose of ABS. If you are in an emergency braking situation, you need to steer out of it.

It's not supposed to kick in under 10MPH, but I can assure you that it does.

My previous car had ABS and it didn't act like this even with AS on them. I have found that when the ABS kicks in on the IS, the brake pedal becomes had to press, but if you fight it, it does respond quicker. I also turn the front wheels very slightly left and right to provide more resistance which helps slow down your momentum. Don't turn too much, though. Think of it like being on skis regulating your speed. ABS helps maintain steering control, not stopping power.

The problem isn't so much that you are sliding, it's that the ABS kicks on too quickly and won't let you actually stop, sliding or not. Once it thinks you are sliding even a little, the ABS keeps going even if you regain grip on the road. In fact, ABS will kick on even if the roads are dry and you press the brakes too hard. You have to let off the pedal and brake again.

I plan to have it looked into by a mechanic to see if there is some way to reduce the sensitivity. I don't think there is anything wrong with it. They are operating as designed. But the real world says that when you need to stop, you need to stop, sliding a little or not. You are always going to slide a little in the winter. We are used to that.

Retroplay

Here's a good description of the purpose of ABS. It is not designed to make you stop more quickly, but to maintain steering control. In short, you just have to drive an ABS car a little differently.

http://www.freewayinsurance.com/blog...tilock-brakes/

And this one causes a little chuckle out of me:

"Antilock brakes don't reduce fatal crashes; people in cars with antilocks at greater risk — but it's unclear why"
http://www.iihs.org/iihs/news/deskto...ts-unclear-why
(Maybe because it doesn't let you stop when you need to stop, perhaps?)

Retroplay

One thought (and might not be the case) would be to have the brake bias checked. ABS kicks on when it senses that one or more wheels are going slower than the rest. It sees the still rotating tires as slipping on ice or whatever. However, if your brake bias is not set up properly, one or more wheels might stop rotating faster than the others triggering the ABS. Ideally, the brakes should work in perfect unison, all applying the exact same pressure at the exact same time.

If somebody had work done on the brakes recently replacing only a couple sets of pads or rotors and did it themselves, not following the elaborate brake maintenance procedure, then that might result in wheels that brake faster than others.