Oh wow! Brake fluid flush.
 

So I thought I'd make a post for history and searching sake.

2004 ls430 176k miles

Symptoms- brake pedal would go down far and it seemed to take a lot of force to actually stop or hold the car still when cold. Replaced front pads and rotors and same result. (They were warped anyway)

Also to note, when stopping if I let off the brake pedal and quickly hit it again I got a higher pedal.

The work - flush brake fluid, pumping out reservoir first, refilling with new fluid and working in the common "farthest caliper from the master cylinder" method. Fluid was original, 176k mile fluid.

The result - brake pedal is MUCH more constant/ consistent. Still the pedal is a little low, but pressure is higher when it reaches that point. Adding more pressure results in much better stopping power and it doesn't need much more travel to add pressure. I had an issue of feeling like I was going to rear end people and really had to stand on the pedal from a normal stopping distance. Now I'm stopping well before that point.

Cost - $7 ( 1 qt of brake fluid), hose to put on bleeder and run to old oil jug 3/8th I think. I had some laying around.

Tools- fluid transfer pump (the one you need to fill the rear diff), 10mm box end wrench, Jack, Jack stands, 21mm socket or factory tool kit lug nut wrench.

Time- 45min to 1.5 hours. 2 people needed. Buy a brake bleeding machine and it will go substantially faster and only one person needed. I could not find speed bleeders identical to whats on the Lexus.

Hopefully this helps someone out there. Super easy/cheap and best result ive had yet for brake pedal feel on this car.

I believe johnhav430 found a fitting that works for lexus vehicles if my memory serves correct.

I saw some m10x1.0x34.44. Probably $30 for the set. Factory size is m10x1.0x35.9. I'd be with a longer bleeder, not sure how the shorter bleeder would work. Still saved 20 bucks though.