ebear695

Hello all, have recently aquirred a 2002 SC, I've had a 05 RX since new. Love both, however, something different with the SC, during braking there are times when the brakes seem to stick or nearly operate themself causing the car to come to a firm stop. The system doesnt "lock up" but Ive been able to remove presurre from the pedal and the brakes are still applied, they seem to release when the engine rpm is applied, this cant be normal for this car, does it have something to do with VSC, or is it time for a paid dyagnostic.

Lot of great info here, thainks

WIL44

Hi ebear

Welcome to CL

This is certainly 'not normal' and sounds pretty dangerous. I would get it to your Lexus dealer asap.

Best regards
Steve

kjcole

Agreed. Not normal, absolutely not normal. Any pulling when the car does this? If so, suspect sticky caliper piston. If calipers look good, then I'd also would be looking at things like VSC.

Harold57

I agree with Steve and kjcole. This is probably the result of sticky calipers. You will likely need to get your disc machined afterwards also. You should attend to this quickly before it causes more damage or a wreck.

ebear695

Thanks for the imput, took the car to my repair shop, he took for a ride, stated that the feel of the brakes is normal for all the SC's that he has driven and worked on, I guess something to get use to. if not, time to DIY with new pads and rotors, not that expensive for DIY

Thanks again

WIL44

Hi ebear

If you are describing how the brakes feel accurately and your repair shop says 'it's normal', I would find another shop, because it is not.

Best regards
Steve

kjcole

When you hop in a totally different car something like brakes that feel sticky or wacky in any way just jump out at you -- which is your current experience. You said, "there are times when the brakes seem to stick or nearly operate themself causing the car to come to a firm stop" Wow! there is something wrong. Have some friends whom you trust drive it, but don't talk about the brakes so you bias them. Just ask them to drive it and give you a critical evaluation of the driving experience. Better yet, I don't know where you are in California, but chances are good you can find another SC430 to drive and compare.

If that doesn't resonate with you, here's my experience:

My 2002 SC430 was new to me two summers ago. This was the first Lexus I ever drove. I flew from Iowa to Houston with my 18 yr old son, checked over the car, drove it, completed the deal and drove it back to Iowa. At no time ever did the brakes feel like they operated any differently than I expected. The braking never really registered consciously, it just happened appropriately. I've been a licensed driver for 42 years and there is nothing unusual about SC430 brakes, or they would have jumped out at me over that first 5 minute test drive.

FLYCT

The car stays put sometimes when pressure is removed from the pedal? SOMETHING IS NOT RIGHT. As others have stated, it sure sounds something like a sticky caliper to me.

I have 2 SC 430s and the brakes are as normal as any car I've driven in the 50 years I've had my DL.

At a stop sign, if I slightly remove pressure from the brake pedal the car rolls 100% of the time on a level road.

Come to Florida and I'll let you drive one of mine to compare.

JR

ebear695

thanks again for ypour imput, you're all right, it time to jump under the check the pads and rotors for myself, pads, rotors and clear the calibars, At least i"ll know what I have in there

kjcole

Not sure if master cylinders ever stick. Also, check the color of your brake fluid in the reservoir. Should be clear.

Kelly

thombiz

My opinion is you have a sticky caliper for a couple reasons. First the background info. Brake fluid absorbs moisture out of the air. This happens slowly so it takes time. When enough moisture comes together, it forms a droplet. Water is denser than brake fluid, so it will sink to the lowest location of your braking system, the calipers. The calipers are cast iron and the water will cause the cast iron and perhaps the pistons in the caliper to corrode over time. This corrosion will tend to cause the piston to hang-up and act irratically. Sometimes, it will take excessive pressure to make the brakes work, and other timess it will hang up then suddenly release causing short harsh stops. Sometimes it will just lock in the full braking position, which will cause the rotor to heat up and likely warp. Because your car is a 2002, it is a prime candidate for this to happen. If your car was several years newer, not so much. It is fairly common to see this problem on 8-9-10 year old vehicles, especially if the owner has not been dilligent about flushing the brake fluid. If the car sat for a while before you purchased it, then that could have exacerbated the problem. That happened on my sister-in-laws Tacoma. My recent experience is that there aren't many places which still turn rotors to resurface them. The cost to resurface is almost the cost of new replacements. I tend to order the best aftermarket rotors I can find and go with rebuilt calipers from the most reputable rebuilders.

ebear695

i'M WITH YOU on that Bob . planning on jumping into the front this week, cleaning up the calibers and seeing for myself the condition. probably a fluid flush as well. After a few more statements by my mechanic other that the "brakes are normal", its time for a new person.

ebear695

so im going to clear the calibers tomorrow, two schools of thought, use brake cleaner or soap and water, any thoughts

thombiz

The corroded parts would be internal and unaccessible without disassembling the caliper. Just cleaning the outside will not help. If it were me, I'd go to www.raceshopper.com or one of the Lexus parts sources found on these websites and order replacement calipers, rotors, and pads. At raceshopper.com, I'd call them and get their recommendation. They are knowledgable and helpful and carry some of the best and most reputable brands, and their prices are hard to beat.

ebear695

OK, tore down the brakes, found the front brake pads near new and the rotors also looking new with no wear, checked the caliber pistons for operation and cleaned the outside with cleaning fluid, then flushed the brake fluid really well. Did the driver side first, buttoned it up. did the pass side and noticed that when the the brakes were applied both pistons would extend, when the pressure was released i could see the pistons retract a touch. Drivers side did not do that!

Went back to the drivers side, extended the pistons and cleaned them again the checked the pistons extend under pressure and retrack when released.

Test drive, all is well, they operate as they should, no pulling, sticking and release right now. yeah , not sure the cleaning did that much, but the fluid flush i think was everything, old fluid was on the dark side, needed to be done!

Thank you for all your comments and imput.