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momike98
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HI, I OWN A 1992 LEXUS LS400 AND I SEEM TO BE GOING THROUGH BRAKES LIKE CRAZY, I REPLACED THE FRONT 2 ROTORS & PADS WITH LEXUS PARTS. THEN DROVE ABOUT 1000 MILES AND FRONT BRAKES STARTED TO VIBRATE AGAIN SO I WENT OUT AND BOUGHT 4 NEW DRILLED& SLOTTED ROTORS OFF E-BAY FOR $249 FOR ALL 4 WHICH MY MECHANIC THOUGHT WAS TO CHEAP TO BEGIN WITH, THEN AFTER ABOUT 500 MILES I STARTED TO HAVE THE SAME VIBRATION PROBLEM AGIAN ANYBODY HAVE ANY SUGGESTIONS?

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Wish I could offer a suggestion; I have similar problems when driven hard. Keeping off the brakes by changing down - o'drive off under 80 then coasting, down the auto box and using brakes only when necessary they last about 6,000 miles. Using foot-handbrake instead of footbrake when stopped helps reduce rotor distortion as the new pads hold heat a lot more. Have had my LS400 since 1992 - 380,000 miles - and have replaced countless rotors (discs) but only in the last four years which corresponds to hardened pad material as asbestos removed. Basically the hard driving days are over as unfortunately these early 400s are under-braked at the front and a nightmare with new pad material regrdless of rotor type / cross-drilled/whatever. Any suggestions also welcomed.

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  • 2 weeks later...

I've had similar brake problems on my 90 130mi ls400. I had the brakes resurfaced and what not at lexus and it still kinda shudders i dont know why. Best thing to do is to keep the brake fluid level. The LS is a heavy car so there is a lot of pressure on those front discs. That sucks that aftermarket prouducts don't help

As far as "downshifting" goes I dunno...I wouldn't necessarily reccomend it. I'm not a pro mechanic or anything but my experience with cars tells me that the tranny isn't made for slowing the car down; I'd think that using the tranny or the footbrake would put premature wear on parts - meaning you'd have to replace a tranny rather than brake pads.

Question for drbob: What does this mean? The asbestos thing...

"nd have replaced countless rotors (discs) but only in the last four years which corresponds to hardened pad material as asbestos removed"

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All I can say is that it works for me for the past couple of years of usual very high mileage being suitably mechanically sympathetic, rather difficult after racing sports cars for 30 years, but coming off the power long before previously necessary, flicking off the o/d, giving a brief throttle blip before 3rd engages and the same to 2nd is gently seamless extending brake life and has removed the judder when braking completely. Ridiculous to have to compensate at all in this day and age.

I didn't mean using the handbrake to slow down, just when stationary in preference to the footbrake as using the footbrake when stationary keeps the pads on the discs so the heat retained in the pads distorts the discs.

In Europe astbestos is no longer permitted in pads and whatever is used now eats discs by comparison.

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  • 1 month later...

is it not an option to fit bigger discs? they should be less stressed due to their bigger size and therefore last longer :question:

just trying to give myself hope, as I'm not one to drive slowly and I dont want to have to spend £160+ on new brakes every couple of hundred miles! :crybaby::unsure:

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  • 1 month later...

I have found that as the car grows older, sometimes the calipers tend to stick. This is especially a problem as the pads wear and the caliper piston has to travel farther out in the cylinder bore. When they don't retract properly, it eats the pads. An easy way to tell if they are sticking is to feel the wheel after a short run. If the wheel is really hot, or if you notice one side is much hotter than the other, you may have this problem. My 1990 400 completely wire out my right rear pads in about 3 months. I was able to clean it up they work okay now, but I don't like that stuff. I have a new caliper in the trunk and will replace it this week. I paid $94 for it. Dealer wanted $365.

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  • 5 months later...

I have 230000Km on my 91 LS400 and 110,000 Km on my second set of pads, which I bought from Lexus Canada. The first set had more than 110,000Km on them when a caliper seized and caused a pad to wear out early. The fix for seized calipers is to remove the pistons and sand out the outer lip of the cylinder where the rusting and jamming occurs. Next I completely fill the rubber boot around the piston with brake silicone lubricant, thus reducing or eliminating the contact with salt water. So far I have gone 4 years with no sign of seizing.

Flush your brake system once each spring. Only takes an hour and a little brake fluid. Much better than badly seized calipers, or even worse a corroded ABS system.

The way I drive, not heavy on the brakes, slowing down early for lights that are going to be red anyway, I don't accumulate much brake wear. I also use my gears for long downhills, rather than the brakes. If you drive aggresively I'm sure the pads and disks won't last long.

A major cause of disk warping, and the resulting vibration, is excessive use of brakes on long steep downhills, rather than using a suitable lower gear. You have to get the engine above 1800 rpm where the fuel cuts off, and on a steep hill 3000 or 4000 rpm for max braking.

If you have hot brakes and drive thru a pool of water the sudden cooling will warp disks pretty quickly. :crying:

I have followed cars driving down from ski mountains and seen smoke and steam pouring out from the brakes. Relying entirely on the brakes on long slow steep downhills can leave the brakes glowing red.

Ernie in Vancouver BC Canada

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  • 3 weeks later...
  • 1 month later...

:driving: -------- :driving: -------- :driving:

Hello LS 400 owners !

I own a 1992 LS400 since over 10 years (I bought it with 18.000 km - about 11.000 miles) and I experienced the same problem with the brakes.

Because the first edition of the LS400 from 1989 to 1992 has been designed for the USA-market only, the brake-system is not suitable for Europe.

Well, if you drive like the Americans - max. speed 60 miles per hour - then it is suitable.

But since most of us like to put the hammer down on the highway, we have real problems with this brake-system.

So I checked, which car on the market has the best brake-system of them all and came up with the Porsche 911 Turbo.

I bought the front brake-system of a 911 Turbo in the hottest version: the 911 Turbo GT2.

Then I had all the necessary pieces made to adapt this brake system to the LS400.

It took one whole week working on the lasted numerical control machines and on a technical PC to develop all pieces, then test them on the car, go back to developing work, go back to machine new pieces, and so on .....

All made of the finest aluminium.

Topped it off with stainless steel brake lines.

And since then I own the best braking LS400/LS430 in the world.

Should I ever have to replace any part (pads, calipers, discs,....) - I just drive to the next Porsche dealer and have the parts installed.

But until now I never had to replace anything, not even the pads (I have now 101.000 km on my car, which equals about 63.000 miles).

Of course this whole procedure was VERY expensive, but it was worth while.

I enjoy braking now and the car stops in an incredible short distance !

I remain with LEXUS - regards

Mike

:driving: -------- :driving: -------- :driving:

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Wow! i've spent a kings ransome on mine, but i'm sure i wouldn't go that far, unless it was fairly new, which mine isn't!

but it begs a question; if toyota want to continue to enjoy the reputation that lexus cars are ultra reliable, they really should come up with an 'at cost' replacement for the calipers and 'rotors'. and while they're at it, they could supply PSU's and displays for the instruments, again at cost.

despite everything, i still think the LS400 is a great car.

are the latest 430s suffering from crap brakes in the same way?

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  • 1 year later...

Try getting the discs machined ON THE CAR by a shop with a Pro-Cut lathe. This fixed an identical problem I had on a (UK) Ford Granada. Probably best to wait a couple of hundred miles after fitting new discs so as to let them warp to their natural shape (given the stresses inherent in the metal). Then get them skimmed on the car. The advantage of this is that the lathe is referenced to the axis of rotation, and takes into account any unevenness on the rotor mating surface. Ensure, too, that you only use a torque wrench to tighten your wheel nuts.

Rich

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