Benjamin T

iTrader: (2)

i have a 99 lexus gs400. stock calipers, hawk pads, powerslot rotors, goodridge ss brake lines, motul fluid.

i searched, but this was all i could really find:

https://www.clublexus.com/forums/sho...light=bleeding

this is what happened...

a few months back, i was diagnosed with a seized left front caliper. was not rebuildable. i bought a rebuilt caliper from a parts store but it rusted up quickly and i was forced to buy a used oem non-rebuilt caliper from an 03 430 that was in better condition.

the mechanic bled the brakes using the regular manual method with the car running, but the pedal went all soft and braking performance was poor. they were bled a second time, this time with a power bleeder, but the only caliper that had air coming out was the one that was replaced, and it was minimal. there wer no air bubbles coming out of the other 3. braking performance improved somewhat, but was far from being good.

current symptoms:

there is no linear braking for the first 2/3rds of brake pedal travel. the car just sort of vaguely loses speed. in the last 1/3rd of pedal travel, the car will abruptly brake really hard and it's difficult to modulate, sometimes even tripping the abs. if i pump the brake pedal when at a stop, the pedal feel improves, but after several subsequent stops, it goes back to being bad again. i haven't experienced any warning lights on the dash for abs or traction control during either driving or when it was at the shop.

when brakes are stone cold, i've have to use a lot of force on the brake pedal to slow down on hills. after about 2 stops it gets better (relatively speaking).

now the mechanic suspects i have air in the ABS system somehow and wants to do what the URL link above says, and it's going to be expensive. i was hoping someone else here had the same problem fixed and can help me before i potentially waste more money at the stealership

thanks in advance...