Does it firm up after several pumps of the pedal?
Has the fluid ever been changed?
Has the system ever been bled?

 

 

When you compress the pistons, the pedal is usually very soft initially until you pump it several times and then that should be it.

If the brakes were bled, then there is probably still air trapped in the system and the whole system should be bled again. If the problem is still present after that, then I would investigate the master cylinder.

 

 

 

Who did the job...hate to say this but this would always happen when my uncle did brakes and say a caliper were replaced, he would do the 2-man way and I think he would close the bleeder slightly after the other man released the pedal....which I why I bought a Motive to do away with needing someone on the pedal (I heard there is also a tendency for the person to step so hard that they could damage the seal to the master). Prolly just need to bleed again and you'll be fine....

 

 

Here's my take....for over ~7 months after the brake job, your brakes have been fine. You went on vacation for 3 weeks without the LS. Did you drive another car while away, then return to the LS and drive it, then (involuntarily) compare the brake feel of that car to the LS?

I say that because 7 months later is a LONG time to recognize something went wrong from that fall 2017 brake job. It's possible your neighbor crawled under the LS and cut a brake line when you were away, but that's only in the movies, lol. You also said your brake oil level is fine, so you can eliminate the low fluid theory.

Is it possible you're comparing the rental or whatever car you might have driven for the last 3 weeks to the LS? Rain has nothing to do with this.

 

You are absolutely correct I think after driving a 2017 ford fusion for two weeks straight I probably was comparing , drove my LS to work today and everything seemed like it was before loll

 

It's true. For 4 1/2 mos. in 2016, I had a 2016 BMW 328i loaner. Everytime I would get into my wife's GM SUV, after driving the BMW for 5 days, I would say wth happened to her steering, is it broken? It's so heavy.

Not making it up, it would seem as if something were wrong with my wife's steering.

Contrast--if I were to drive my 2007 BMW 335i coupe, then get into my wife's SUV, the steering feels light. What does that say about the 2016 BMW....but if we switch back and forth daily, etc., imho our involuntary muscles adjust and we don't think about it...

 

My brakes have been acting strangely the last year or so. At a stop light I have to push really hard sometimes to get it to stay completely stopped. It will start to inch forward unless I keep applying increasing pressure. When I finally do remove my foot there is a squeaking noise from the brake pedal.
I had new rotors and pads put on but it made little difference. They also bled the lines and replaced fluid. What could it be? Master cylinder?

 

For 1.5 months in 2010, I had a new Nissan Altima as a loaner. The brakes on the Altima were very touchy/twitchy, very much like a Mercedes C or E-class I once test drove at an auto show. After I got my 2002 LS430 back, I thought there was something wrong with my brakes because of the much lower brake catch and significantly longer pedal travel. However, I quickly realized that I had become too accustomed to that Nissan Altima and its twitchy brakes. The brakes on my LS430 were the same as always, powerful when needed to be, and smooth and gradual otherwise. In my case, the Altima had rewired my muscle memory.

 

Have you seen my information consolidation at https://www.clublexus.com/forums/ls-...ml#post9850497 ? That should cover most problems relating to low catch and soft/spongy brakes.

 

No, there are so many posts, I was unable to find it. Thank you!