Front Brake Rotors

[mluc8]

I have a 2001 LS430 and the brakes need some help. There is pulsating when applying the brakes especially when slowing down from a higher speed. I've checked some of the auto supply stores and they don't seem to stock them. Am I forced into buying from the dealer? Does anyone know of a good source for them?

Thanks.

[FEASTJAPAN]

I have a 2001 LS430 and the brakes need some help. There is pulsating when applying the brakes especially when slowing down from a higher speed. I've checked some of the auto supply stores and they don't seem to stock them. Am I forced into buying from the dealer? Does anyone know of a good source for them?

Thanks.

Sounds like the rotors are warped. May be just age or you recently just overheated the pads. Been there...it stinks!

There are many rotor options for the LS430 including drilled/slotted rotors.

[etex]

Try tirerack.com. Thhey carry Brembo rotors.

Good luck.

[VMF]

first of all, rotors dont warp, when you overheat the breaks, residue from the pads gets accumulated on the rotors. there were many threads like this here before. many mechanics tell you that you have to change the rotors so they can make some extra money on you. just have them machined and the problem is going to go away.

[cardona6569]

Hello:

I totally agree with VMF unless they been machined too many times and became too thin to be done again. But definately all you need is to have them machined and maybe the pads grind a little or changed and you should be ok. Try to roll a little when stopping at a light so the head can disipate better.

CPR

[python]

Hello:

I totally agree with VMF unless they been machined too many times and became too thin to be done again. But definately all you need is to have them machined and maybe the pads grind a little or changed and you should be ok. Try to roll a little when stopping at a light so the head can disipate better.

CPR

he is right, just have them machined.......as far as rotors not warping? ive never heard that in my life and have either been a mechanic, worked on cars or now i work at NAPA auto parts and deal with auto shops every day of my life and that is news to me.......ill look into this and find out for sure

[nc211]

On Friday, I probably would of disagreed with VMF.. But after working the rear brakes of my 4runner yesterday "Saturday," thinking they were warped because I had bad pulsation in them, now, I'm in agreement with VMF. Bought my 4runner with 52k on the clock. Now it has 57k. Everything about the car is stock, everything. Whoever owned it prior, drove it in a straight line, for a long time. Tires have plenty of tread left, pads "at least the rears" have 7mm left. And upon thinking the rotors were ready to be replaced, I checked the size of them...a perfect 18mm, not worn down. But, upon taking them off, I easily noticed, especially on the back side, a bunch of "pad marks" all over them. I ran my hand on it, and I could feel the bumps from the pads. Took them up to the shop, they machined them, and all is like new again. They took off a hair's width. Said they were "filthy", which is the first time I've ever heard some describe a rotor to me. Filthy? I asked.. I did clean them before taking them up. He said "no, not dirty, the surfaces were coated with grime." That quote, matched by them still being at 18mm after 57k miles...makes me lean towards VMF's diagnoises.

Learned something new yesterday....

[TexasLexus94]

I just changed out the rotors and pads on both my little Mazda MX-5 as well as my 94LS 400. I always install new rotors, rather than grinding the old ones, because I figure that if my old tortured body has to get down to change out the pads, I might as well put in new rotors, and save the old ones for possible grinding and re-use.. Especially since I install ceramic pads, which I believe wear out rotors a little faster, but don't squeal like semi-metallic ones often do. The rotors and pads cost me $100-125 total each car, but the resulting smooth, quiet braking is great. BTW-the previous owner of my Lexus had 3 brake jobs at the incredible Lexus stealer between 45,000 and 95,000 miles-They ground down the rotors each time, and charged 6-1/2 hours labor each time! I'm convinced the dealers know that their repair including grinding of the rotors will result in more business shortly down the road, since it is such a heavy car.

Hey, NC211, nice to see you're still contributing to this forum, even though you must have sold your Lexus. You are forgiven. As you might remember, I'm a blue state Democrat-but this year, I don't have a clue. Best of luck...

[eddielasvegas]

I just changed out the rotors and pads on both my little Mazda MX-5 as well as my 94LS 400.

Nice to see there's another Miata/LS 400 owner. I was wondering if there were others besides myself.

Eddie

[nc211]

I'm a blue state Democrat-but this year, I don't have a clue. Best of luck...

Ohhh TexasLexus... I could so easily make a little humor out of this statement! Hahaha...

J/K

Thanks amigo, always nice to feel welcomed, even if I don't have keys to the front door anymore. I figured posting "I sold my LS" would grant me less shame than "the automatic head rest is stuck due to my boy's dirty diaper, among other things?", and "how do you get pees and carrots out of the cracks of the center consol?" or "crayon marks on the headliner..I hate Barney the Dinasor". And my favorite "how do I get that Lexus leather smell back?"

[TexasLexus94]

Yes, EddieLV, I have a Summer car and a Winter car, even though we really don't have much of a Winter. The most important thing is to use both cars year-round. I wanted to add that the parts cost I listed for the brakes were for the front ones only-the rears seem to last much longer.

Hey, NC211, you sound like a great father. Be sure to give your children-male or female-access to your automotive expertise. We'll always have mechanics-although I think they'll be more like geeky electronic techs than grease monkeys-we dinosaurs are falling beside the wayside....Whatever happened to "points" and "condensers"??

[4.0 LS TECH]

Rotors don’t warp? I’m confused, does this mean my dial indicator is liar when I check the run out on a rotor and it shows variations in the surfaces? Yeah I’ve seen them become glazed and get buildup from pads that sometimes cause them to feel warped.

But according to the service procedures supplied to my dealership by the manufacturer, we can check a rotor to see if it is warped with our dial indicator.

And telling a customer to change the rotors so I can make some extra money. No, I’d rather turn the rotors on the lathe and charge more time. I don’t make money off of the parts, i make it off of the labor. that’s why I charge 1.5hours at my work for a brake job. Don’t tell people it only takes half an hour to do it. We all gotta make a profit, that’s why it’s a business.

[TexasLexus94]

I'm certainly no expert on brakes, but grinding rotors means they become old rotors-since installing new rotors with new pads means you have new brakes. Simply put, I question whether new pads with ground rotors last as long. The previous owner of my 94LS paid through the nose for brakes with ground rotors that lasted about 10,000 miles-three times. At a Lexus dealer. My new ceramics with new rotors work perfectly. I'm curious to see how long they last-on both my cars. What I've found is that if they work great-with no noise or shudder at installation, then you're all set to go.

Once, I did install new rotors on my Lexus that still had a squeal with new semi-metallics. So I installed the old semi's; they didn't squeal-but they developed a shudder at high speed 5,000 miles later. Food for thought.

Hey, NC211-who's your candidate? Please don't say Huckabee-I won't say the H chick....

[dnaglich]

I just changed out the rotors and pads on both my little Mazda MX-5 as well as my 94LS 400.

Nice to see there's another Miata/LS 400 owner. I was wondering if there were others besides myself.

Eddie

I have a 94 Miata and a 95 LS 400. Great combo!

[PureDrifter]

I'm certainly no expert on brakes, but grinding rotors means they become old rotors-since installing new rotors with new pads means you have new brakes. Simply put, I question whether new pads with ground rotors last as long. The previous owner of my 94LS paid through the nose for brakes with ground rotors that lasted about 10,000 miles-three times. At a Lexus dealer. My new ceramics with new rotors work perfectly. I'm curious to see how long they last-on both my cars. What I've found is that if they work great-with no noise or shudder at installation, then you're all set to go.

Once, I did install new rotors on my Lexus that still had a squeal with new semi-metallics. So I installed the old semi's; they didn't squeal-but they developed a shudder at high speed 5,000 miles later. Food for thought.

Hey, NC211-who's your candidate? Please don't say Huckabee-I won't say the H chick....

they last just as long.

read up.

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

[SRK]

Well I am a brake expert. I don't know who this Carrol Smith guy is, and just why he wants to display his ignorance on the web, or why so many people point to this one person's advice as if he's the pope or something. Smith should phone the manufacturers of brake lathes and tell them they should be out of business. Brake rotors warp, drums go egg-shaped and bell-mouthed, and both develop surface irregularities due to pad material and road dirt.

Measuring brake rotor run-out is easy, and should be done every time. Any good tech must have a dial indicator, or access to one.

Most factory service manuals specify the maximum allowable run-out and on a Lexus it is very small - a matter of .003 inch or so before pedal pulsations are noticeable.

I have machined lots of warped rotors, AND stayed well above the minimum thickness, AND returned the rotor to service. But if the calipers are sticky and the brakes drag a bit, they'll warp again. A warped rotor is a symptom, of either driver abuse, or poor mechanical action that prevents the caliper from releasing all the way. The early LS brakes were undersized, and the wheels too restrictive to air flow - they warp. My GS has huge brakes, lots of wheel open to the air, and the rotors are original and un-warped at 11 years of age. My LS now has 16 inch wheels, and turned rotors, and guess what? They don't warp anymore.

Maybe Smith is Al Gore's illegitimate brother or something - that might explain why everyone seems to get on bended knee and listen to the silly bugger.

[curiousB]

I recently had front rotors turned and new pads added. My recent set of new tires came with a 17 year old tire installer and his air impact wrench playtoy. The rotors were warped within 6 weeks of the new tires. Anyway when I went back and told them about this they were good enough to assign a senior tech and turned rotors on their dime. Since then the vibration (and pedal pulsing) is gone and stops are very smooth. So I have just had front rotors turned (after they were warped so probably had to be cut a little more to get warp out) and it all worked out fine

The rear rotors were another story. Absolutely rotted out with holes in them. Don't know if its the winter salt they use in IL or just bad castings. Anyway went to dealer to get new rears and after quoting the lexus ones at $180 each he also quoted me a non Lexus brand. I viewed it as an admission of guilt that (a) Lexus rotors are crazy expensive and (B) other branded rotors can work just as well.

I ended up getting off brand rotors at a foreign car parts shop for about $60 each and they have worked well going on 4 months. I did replace pads all around with genuine Lexus pads as they are priced fairly at various internet parts outlets.

So turning rotors can work just fine. So too can secondary brand rotors.

[TransAm12sec]

I don't know who this Carrol Smith guy is, and just why he wants to display his ignorance on the web, or why so many people point to this one person's advice as if he's the pope or something.

Carrol Smith is a well know and respected driver in the racing industry. He passed away in 2003, however much of his written knowledge is still applied today. His most popular book is Tune to Win, with other versions such as Drive to Win and Engineer to Win. I briefly skimmed over the article, and I don't believe he is saying rotors are never uneven and there is no need for rotors to be turned down, but the reason for the increase tolerance in the rotors is not the rotors itself being "warped", but the friction pad material not being applied evenly to the rotor for a few reasons, causing a pulsating pedal, or the term "warped rotors". It seems like what some people will call a warped rotor, he considers uneven deposition, but doesn't consider the original cast rotor as "warped".

"In fact every case of "warped brake disc" that I have investigated, whether on a racing car or a street car, has turned out to be friction pad material transferred unevenly to the surface of the disc. This uneven deposition results in thickness variation (TV) or run-out due to hot spotting that occurred at elevated temperatures."

http://www.carrollsmith.com

[SKperformance]

I agree rotors do warp but are not the blame for pulsing that mechanics throw at them as the failure.

Rotors do warp as anyone who has used a lathe to cut them can see as it cut material from one side and misses the other completely .

It is alot of old material causing an uneven surface causing the effect which once removed works well.

[curiousB]

Can we clarify here? Are you saying:

1. The deposition of pad material creates uneven thickness spots on the rotor and this uneven “topography” results in vibration or pulsing from the brakes. In fact the rotor may not even be warped. or
   
2. These depositions create different thermal characteristics of the rotor which cause uneven heating under use and this uneven heating leads to warping of the rotor and the resulting warped rotor lead to pulsing brakes. or
   
3. Even with a warped rotor it isn’t the warpness (run out) of the rotor that creates the pulsing, it’s these islands of deposition that grab the pads to create a pulsing sensation.
   

If 1 or 3 are the answer it sure paints a dim view of semi metallic pads for these cars, Ironically its common to find numerous such pads available at shops and on line and they’re often promoted as upgrades.

Just trying to understand the failure mechanism better.

[SRK]

I have noticed, as have others, that if one washes a car and then puts it away without driving it for a few weeks, or parks a car outside for an extended length of time, that rust will develop between the pads and the rotor face. This rusty "patch" will cause pulsation for a while, but normal braking action will remove it in time. I have NEVER seen pad material deposited on a rotor face - in fact if one simply sprays water on the surface and waits about an hour a thin film of rust will develop ( brown stain) that proves that the water had access to the iron surface - no deposits at all.

Most pads are somewhat abrasive - Lexus ones being only slightly so - and therefore I can't see how any material could be deposited on the surface. Cast iron is the rotor material of choice because of it's high co-efficient of friction - far higher than steel - and most pads are designed to "bite" into it to provide extra friction. So the pads wear at a rate somewhat faster than the rotors, but most rotors are worn out after two or three pad sets. Mercedes and Volvo are notorious for rotors that are worn below maximum after one set of pads, maybe two.

I'm going on my experience and observations after many years of brake work. I've yet to see what Smith is talking about, and I am even more amazed at the response to his claims, which is mostly uncritical belief rather than evidence.

[curiousB]

I tend to agree with you SRK. Pulsing in the front when braking and a shimmy in the steering wheel is due to rotor being warped (out of plane). The forces at play and the natural wiping action of a pad against the rotor would seem to debunk this mystical deposition theory. I thought I read somewhere Toyota is so particular about run-out that they recommend machining rotors on the car (with special and more difficult to use lathe) so you net out any tolerance stack up from to the hub and the mating of the rotor to the hub. Furthermore 0.003" is apparently enough run-out to start feeling pulsing in the front end. That isn't a lot of run-out.

You don't machine rotor to clean them. You machine them to return them to a parallel on plane surface free of gouges.