hhenry510

Does anyone else Lexus LS430 have this problem? When I drive my car and approach a stop sign or start braking towards a car the vehicle jerks forward. It's been acting like this for almost a week now. Do anyone know what's the problem is or can someone help me out.

sha4000

iTrader: (1)

I can't quite picture what your saying. Could you describe it a little more in detail?

Johnhav430

What car did you come from to the LS, this will be a tell.

I think what you describe is 100% normal, when we got this car in October, and my wife and I drove it, the car felt divey. For real, your driving style adapts to it and it smooths out. If my wife doesn't drive the car for a week, she'll ask if the brakes are ok. They are about 95%, flushed by the dealer in Oct., basically new rotors/pads front, pads rear, that's just how they are.

For example, many people, when they take a lap in an autocross with a car they're not familiar with, there's a tendency to let off the brakes abruptly, not smoothly. As they take more laps, they get used to the car's behavior, and the action is smoother. I was hoping that this issue was caused by lower control arm bushings being shot, but it wasn't the case.

The problem imho lies in the fact that the LS has below avg. handling, it's designed to ride like a pillow in the clouds, it just goes with the territory....my buddy told me before I got it, having owned one, imagine driving your sofa onto the highway, that's how the car will feel.

sha4000

iTrader: (1)

I have to agree with John, my 400 even does this though I don't notice it anymore.

hhenry510

When i drive my car and I approach a stop sign it's jerks a few time until it comes to a complete stop and when I start braking and going under 10 mph it's jerks forward. Every time I brake it jerks a few time. I had a Lexus Gs300 before this and my gs300 was perfectly fine.

hhenry510

I had a 03 gs300 before the ls430. My gs300 was perfectly smooth. When I first bought my ls430 it was really smooth until last week it start jerking when I approach a stop sign or go under 10 mph.

Johnhav430

Gotcha, so we're likely not talking about the same thing....

Your jerking effect is not a pulsation, right? Is your pedal just as firm as it always was (although it's soft compared to other cars)?

my feeling with the LS430 is more like where the car is wound up like a spring so it's more of a throttle effect, and using the brakes.....say the motor were idling at 2000, and you're holding the car with the brakes, and you let it go....(this is an exaggeration of the symptom)....in other words, at a normal idle, the car lurches more than any other car I've experienced, but once you get used to it, it can be operated smoothly without even thinking....as an example, my wife has a SUV, it's an auto, and it rolls back on a hill (believe newer ones have a hill holder and thank goodness we don't as it prolly wears the rear pads). Pretty sure the LS430 would move forward on a hill and does not have a hill holder (could be wrong)....

caverman

Neither one of my LS430 do/did what you describe.

Right off the top of my head, what you're describing to me sounds like warped brake rotors. How many miles are on your car and when was the last time the brakes were changed? Also, when the brakes were changed did they just resurface the rotors or replace them?

If you're a DIY kind of person then replacing your brake pads and rotors is not a hard job. On my '04 I replaced all my brake pads (no rotors) for about $200 for all four wheels with premium NAPA pads. Rotors will probably cost right at or just under $100 a piece (again I like NAPA stuff). If you feel it is the rotors then you could probably get by with just replacing the front two but you'll have to do both pads and rotors.

rkw77080

Can you tell if the timing of each "jerk" is proportional to the speed of the car? If so, you may have a pitted or cracked rotor that is catching the brake pad.

jayclapp

The LS430 does not have a hill holder and it will not move forward on a hill.

Gronemus

I wonder if some kind of fluid contaminated one of your rotors. It might be worthwhile to go out and look closely at your rotors, both sides, front and back.

What year and how many miles do you have on the car? When were the brakes serviced last? Did the brake pedal feel change when this first started to happen?

hhenry510

Thanks everyone for your help I appricated it but I figure it out it was my transmission that went bad 😪

caverman

How did you come to that conclusion? Do you know what it's going to take to fix it?

msitzman

What year is your LS430? I have an 04 and was experiencing the exact problem you described. I had the engine and transmission computers flashed with newer software and it is MUCH better. I still have the jerk for the first couple stops when everything is cold but then it smooths out nicely. If you have an 04 or 05, check out the service bulletin TC006-04 for Shift Enhancement.

I would be cautious with a bad transmission diagnosis. There have been some other threads where transmissions have been replaced and the problem persisted.

Mike

hhenry510

I brought my car to Lexus to see if they can see/fix the problem. They told me that they reflashed the engine and the transmission ecu. When I went to pick up the car they told me the gear one and gear two went bad and the only thing I can do is get a new transmission, they quote me about 3550 for a new one.