DKIS350

Okay so heres the deal...Since the day i bought my IS350 year an a half ago i have had a braking pulsation. The dealer replaced the rear pads, rotors, and calipers (as the caliper slides were seized), and the car was better....but still had a slight pulsation. So they replaced the front pads and rotors. The car drove like a dream for about 1500 miles and the pulsation started coming back. They replaced the pads and rotors under warranty again, and now again, about 1200 miles later, the pulsation is returning. I even took all of the calipers, pins and slides apart on my own to make sure nothing was seized, and that the dealer didnt over look anything. Everything looks perfect.

Im not hard on the car, and I cant say i have EVER warped rotors like this on any other car. I do all highway, with almost no stop and go. I never even warped rotors like this on my 04 GTO which was autocrossed, heavy, and had little tiny brakes.

Any ideas? Could i have a warped hub or something that is only apparent when the rotor warps to the hub after some time???

Im at the point of wanting to trade it for another Lexus. 30k miles a year in a car that always shakes when you stop is getting old.

jallow33

Similar situation here. Purchased my IS350 Last February. After about 5000 miles, warping in the front rotors after dealer changed brakes. I changed the rotors, and followed a break in procedure. 20k miles later, no warping, no pulsating, no vibration, just smooth stopping. Perhaps you need to bed the brakes to match with the rotors so it doesnt develop warping after some few mileage. May be possible case.

Gustavo621

Are you using OEM rotors?

DKIS350

Yes, factory parts only, that way Lexus can continue to help me with this issue. I made an appointment for next week, so we'll see what happens then.

I appreciate any input anybody has before before I bring it in next week. I dont believe its all four rotors warping right now. Mostly feels like its in the steering wheel. First thing I guess they need to identify if its both front rotors that are warped, or just one. Since this has been an issue since day 1 (since i purchased it used) Im starting to wonder if something is bent or damaged. The new front rotors fixed it last time for a few weeks.

getafewliv

They really shouldn't be warping. I brake hard sometimes and have had zero issues and I don't even think the fronts on my car are OEM pads and rotors. They were done just before I bought the car, about 10,000km ago.

+1 for proper bed in procedure. This ensures an even layer of pad material embedded onto the rotors. If this is not done it is often the cause of "warped" rotors.

From what I have read, rotors shouldn't actually warp, it's an uneven pad deposit on the rotor causing the
feeling of them being warped.

getafewliv

Should mention as well, when I had my TSX, I had a similar issue. Rotors would be toast in no time at all. I switched to powerslot cryo treated rotors and hawk pads and noticed a big improvement.

knguyenk

I had have issues with warping rotors where bed-in procedures was neglected. I've also read that incorrect (more like uneven) torque of the wheels can also be the cause, when the installer gets lazy and just guns them tight.

I just recently upgraded my brakes to the IS 350 brakes and made sure to bed-in the brakes and torque the wheels to factory specifications and I haven't experienced any issues with the OEM parts.

Gville350

iTrader: (10)

No mentioning of the front calipers being rebuilt or being replaced was commented on. However, I'd agree the bed-in procedure is a MAJOR fact that helps with this issue.

valeoray

Did you check if the lug nuts were torqued properly? Lexus is only 76 ft-lbs. If over torqued, it would also warp the rotors.

topspeed55

You'd think someone who has auto crossed before would know that rotors DON'T WARP.

http://stoptech.com/technical-suppor...nd-other-myths

DKIS350

You'd think someone who has more knowledge to share with others, wouldn't try to come across as condescending.

For all intensive purposes, Im using the term "warped", the common phrase used across 95% of the automotive industry (though seldom accurate).

Regardless of weather or not the rotors are literally warped, my car shakes like a dog *****ting razor blades when stopping lol.

I think the unknown factor for me is, I don't know if the tech who replaced the pads, did a bed in procedure. I did it when i left the dealer, as thats what i would have done had i done the brakes myself. 6 stops from 35-40mph down to around 5mph using moderate pressure, and 3 heavier stops from about 65mph, down to about 5mph. I also dont know what the tech torqued them down to. Torque wrench? Torque stick? Maybe they just hammered the lugs on with the impact gun set to max at 220PSI. I cant say. I know I've seen some scary stuff come from techs at some of these dealerships that I visit ever other week. I've also seen some techs put out some sketchy work at the dealer I worked for. Nothing scarier than a new young guy who comes into a shop from a tech school thinking he knows it all because hes seen and done it all on paper.

I've replaced lots brakes on the 14 cars I've owned in the last 15 years, never had a repeat issue like this on any of them.

Ill see what Lexus does on Monday. Ill ask what they do for bed-in and wheel torque and go from there. I may end up going with aftermarket pads/rotors and just do it myself at home if time allows.

Any aftermarket recommendations?

getafewliv

For all intents and purposes.

I recommend powerslot cryo treated rotors. They should hold up nicely.

DKIS350

for the grammar correction...

for the powerslots.

NikonGuy

iTrader: (1)

+1000

Get a torque wrench and do it yourself regardless of what the dealer said. Torque it to 76 lbs with star pattern and you should be fine.

The most Important thing is to have equal torque on all lug nuts.

Gregz_IS

excessive lateral runout ... most likely the hub is the issue.

the fix...

http://www.procutusa.com/zipfind.aspx