liquid2

lol, I love my thread title. Down to business, I have a 1st generation ls400, that was handed down to me from my father, who kept it.. forever to give to me. I swear I searched with the keywords Braking and Shaking, but none of the given results were much help

SOO While driving at my normal speed around socal which is around 40-50mph local driving...and I lightly brake, I experience some shaking, and kind of a shaky stop. Like before coming to a complete stop, I can feel the cars brakes "Skip"...and the car jolt just a little bit(I'm trying my best to describe the problem). Another problem which is probably related to this, is that the car does make some squealing sounds while braking. I haven't noticed any vibration...but
The shaking and everything only occurs when I'm lightly braking, If i depress the brake pedal just a little bit more to the point where I'm braking and coming to a stop much quicker, theres a "safe" spot where I don't experience any shaking or squealing.

Sorry If this doesn't make too much sense...Its hard to describe

GS FONZy

iTrader: (6)

it sound like your rotors are f__k up.

PureDrifter

iTrader: (10)

yep, 100% warped rotors.

now, does the vibration come through the steering wheel, the floor/seat, or both?

if the wheel, then its the front rotors that are warped.

if the seat/floor, then its the rear rotors that are warped.

if everything is just shaking to ****, go buy 4 new rotors, they'r all warped.

liquid2

hahahaha, now can you guys help me with a question,

are the rotors for the ls400 on Ebay dependable...and not cheap quality or anything undependable? Would I really save big $ buying online?

mobilyte

iTrader: (3)

guys, it's not always the rotors. he said he hears squealing during braking, might be that he is missing the shims or that they need to be greased. could also be a stuck caliper or sliding pin.

case in hand...i had a horrible brake pedal pulse/rear end shake for a few months. i checked that the caliper pistons werent seized, installed new rotors, new oem pads, lithium greased the shims and sliding pins, cleaned everything and re-greased with synthetic moly grease. i was almost convinced it might be one of the control arms, but they all checked out okay. finally noticed that the rubber boots that hold the sliding pins were torn. without the boots maintaining the airtight seal, the pins were being pulled into the boot and stayed there, they would not extend back out on their own. just installed 2 new boots from the caliper rebuild kit, no more clicking or shaking.

poor rotors, they're always the scapegoat when it comes to our braking system woes

PureDrifter

iTrader: (10)

go buy rotors from Tirerack, they have them for the LS CHEAP. like i paid $65 each for the front rotors on our 2000 LS4. and they were Brembo genuine OEM replacements (non-slotted or drilled)

PureDrifter

iTrader: (10)

please note that liquid said that he is FEELING the car SHAKE, not hearing any kind of squealling. the 99% of the time when you have any kind of constant vibration\shaking\shimmying that happens ONLY when you brake its going to be the rotors (and in some VERY rare cases, the complete disintegration of the pads themselves).

just noise\brake squeal is a whole different beast with MANY different possible causes.

mobilyte

iTrader: (3)

for your reference, from the first post in this thread...

puredrifter, got you down from 100% to 99% sure it's the rotors

the warping rotors issue is a symptom of the underlying problem, not the cause. liquid said that his car doesnt shake under heavy braking, only light braking, clearly not a constant braking issue without regard to pedal effort. he also described feeling a jolt when coming to a stop, which leads me to believe worn bushings in the control arms, strut rod, ball joint, or steering tie rod. it could even be that he has metallic pads instead of ceramics pads causing the problem.

seems like everybody has been conditioned by lexus service advisors to replace, replace, replace, instead of diagnose. he could follow the advice to start with installing new rotors, but i'd bet the fix would be temporary at best and they'd be warped within 1k miles...