AleksLZCR

Recently picked up a seemingly goldmine LS 400 with only 97k on the clock. Driving it home, I noticed the brake was quite soft, but as the brakes also squealed, I just chocked it up to bad pads/rotors. Once I got my funds up, I purchased a new set of pads for the front and rear, solving my squeaking problem, but destroying one of the caliper seals in the compression process. Bought a new caliper and discovered that the fluid may well have been the 23 year old stuff from factory, so I set out flushing all the fluid from the closest to the master cylinder to the farthest, and then bleeding in the opposite order. During this process, i discovered that my master was leaking from where the rear meets the booster and it was sucking air when I depressed the brake pedal and spitting fluid when released. I then purchased a remann from AAP but after bench bleeding and installing, the pedal was still quite soft and fluid still leaked from the exact same location! I then came to the conclusion that perhaps the seals on the booster were deteriorated from all the leaking brake fluid to the point where the vacuum was sucking the fluid past the master seals. Out of a combination of desperation and frustration, I returned the now defunct master cylinder for another remann and ordered an OEM booster off a junkyard 95, as well as two new brake hoses off amazon as I noticed the front was starting to crack. As someone very very new to working on cars, my mechanical experience consisting of an air filter and oil change, re doing nearly the entire brake system has been quite intimidating, and I was wondering if anyone had similar experiences or feedback from their own vehicles. My parts get here in 4 days and Im not looking forward to bleeding brakes for the 5th time in 2 weeks


This is the leak after changing the master cylinder

JohnAndic

oh no... those troubles suck. I have a 97 also. I thought the brakes were a bit soft when I first started driving it but I think LS400's just have softer break feel/longer break pedal travel then other cars. but my car stops good, its a powerful heavy car, you see plenty of em with the hood and bumper all smashed up.

you said you damage the caliper when changing the breaks. you could have done something to cause the main leak sorry to say. seems like you have done a bunch of work and are motivated which is good. good luck with everything. a more knowledgeable guy will be here to help soon

AleksLZCR

Yeah mine was definitely a participant in a hefty front end collision under the previous grandpa, not a bad first car for sub 3k though.
As for the caliper I think it was just old age, the Arizona sun is not kind to rubber. Thanks for the reply though, haven't seen many 400's on the road so glad to see the community exists