Polish Person

I've been trying to figure out if my brakes are pulling, or if it's just the roads around here and if my ABS is working properly, because no light comes on under hard braking. So today I went to a nice, flat, empty parking lot, got the car to speed and slammed on my brakes. The car stopped well enough, but my pedal felt like it was pushing rocks through the lines. It shuttered back and worth, shaking violently. Is this what it feels like when ABS comes on or is something wrong? No light came on in my cluster either, though the car is only a Sport model. The wheels didn't lock either, so I assume it's working at least partially. Any feedback helps! Thanks.

- Arek

RX8Soldier

iTrader: (24)

Uhh... I'm pretty sure that what your saying is exactly how ABS works. The breaks don't lock the tires. It applies pressure and releases it, slowing the vehicle down yet giving you better control over the car (IE allowing you to steer without sliding...).

NgoRX8

iTrader: (1)

lol, "Anti-Lock" Braking System. It's working as intended.

what happens is the brakes pulsate and it can be felt in the brake pedal.

georgemagana

i dont think thats any good. I just got my brakes done and the firts thing the mechanic asked me was if the pedal was pulsating and he said that happens when your rotors (or pads i cant remember) are gone so you should take your car in

ken-x8

That's different from ABS behavior. If the rotors are warped, have excessive run-out or are gummed up you'll get a moderate pulsation at pretty much any pedal pressure. Sometimes there's a little shimmy in the steering. Usually not an alarming effect, and it's fixed by resurfacing the rotors.

ABS pulsation happens when you hit the brakes hard enough that you'd skid if you didn't have it. Owners manuals usually give a vivid description as a warning to just keep your foot on the brake and don't panic.

Ken

jasonrxeight

no light would come on unless a problem
vibration is normal
youve never had an ABS car?

Polish Person

I know the physics behind ABS and how it applies pressure on and off to maintain traction, just like TCS does, but with the addition of throttle modulation. I was just saying that apart from the car shuddering slightly, the tires didn't lock up. I thought that was important to note, since I didn't think my ABS was working, but my car didn't slide. I was thinking that perhaps my rotors were warped or my pads were dead, since that might provide inadequate enough pressure to prevent the wheels from locking up.

My last car was a '91 Trans-Am. It didn't have any driving aids and, honestly, I kind of prefer driving that way. I didn't hesitate to drive that car hard, even when we got freezing rain and snow. Yet I'm afraid to drive my 8 in even the slightest of powder, because of all the threads with people flipping out about how bad the car handles winter weather. I consider it a redeeming quality of the Sport model that it has only ABS and nothing else. Once I get my suspension set-up dialed in I'm going to drive the **** out of my car.

I always thought the ABS light would flash when the system is activated, like in my uncle's SLK32. Both the ABS and TCS lights came on when either system stepped in, or so I believe, but perhaps I'm remembering incorrectly. Thanks though.

jasonrxeight

your trans-am being easier to drive probably cuz it had an open diff. RX8 being LSD is very easy to step the tail out.

Polish Person

It had a LSD in the rear. I wouldn't have tried snow without one.

Does the Sport model have an LSD? I'm pretty sure it's an open diff. I'll change it eventually if it is.

jasonrxeight

I believe all they all have LSD for the 09+

Polish Person

I gotta look that up, but if it's ture, then that's sexy.

Polish Person

Oh, and even if my T/A's diff had been open, it would still out slide, donut and burnout an 8. It's the difference of 280+ lb-ft and about 160. Haha. It only revved to like 5k too, half of what the 8 can do.

maskedferret

iTrader: (1)

ABS engagement to me feels / sounds more like typical gear grinding at the shifter, but at the brake pedal. OP's description seems accurate of what it feels like as well.

Polish Person

You had me worried for a second that mine differed. Haha. ABS is a weird thing.