Hi everyone,
Today i went out to change my front brake pads on my 07 GS 350 Rear Wheel Drive. The passenger was no problem to change. I removed the old pads and pushed back the pistons and installed new pads and hardware. I moved on to the drivers side and removed the caliper, removed the hardware and old pads and started to push the pistons in to install the new pads but as i pushed one side of 2 each pistons in, the other side moved out. Puzzled by this, i tried to push both sets at the same time found that the pistons would not move. Not knowing what to do at this point, i cracked the bleed screw to see if the pistons would retract and they did. I have heard that sometimes the flexible hoses can go bad over time so i ordered new one and installed. Again the pistons on the drivers side would not retract unless i released pressure from the bleed screw. I then disconnected the caliper fluid line and disconnected from the ABS Anti Lock Brake Actuator Module to see if the line was clear and it was. Calipers are expensive and if i change one, then i would change the other as well. I'm torn because i wonder if the ABS Anti Lock Brake Actuator Module could cause this issue. Has anyone had this kind of problem? I just thought to myself while typing this post that i guess i could have swapped sides on the calipers to see if i can repeat it. I will do that just to make sure its not the ABS. Anyway any help would be greatly appreciated.

 

This is normal, all the pistons are connected to the same fluid feed. So if you push one in, the others will push out. When you want to compress all the pistons, you need to use some sort of a clamp and an old pad on each side.

It's easier to have compressed all the pistons with the calipers still attached to the spindle, by removing the silencer/pins on top of the pads, then prying against the old pads. This should give you enough space to mount new pads, or you can remove the calipers after you compressed the pistons.

Kinda like this video

 

ibidu1,
I don't think you understand what i mean. When i compress ALL the pistons (at the same time) they don't move to the flush position, they stay out. Something is stopping the fluid from going back to the reservoir.

 

In that case you can rebuild them yourself, they are not hard to do, and do not take a lot of time. You can more likely find the seals at the dealer or even rockauto.com

Or spend the money on a rebuilt

This video is for a 4runner but its pretty much the same procedure

 

you dont push them at the same time. use giant channel locks, c clamps, whatever you can find to put force on the pistons.. push both pistons on one side of the caliper in completely first, hold that side then push the other side pistons in. the first side will wanna come out no matter how hard you hold it. push them in 1 side at a time while holding the other side in. After 3-4 cycles both pairs of pistons should be completely pushed in.

edit.. you did the other side i guess its seized then... buy new calipers theyre not expensive when you return core.

 

Everyone,
Thank you for the replies. I will most likely replace both sides but i am interested in this rebuild. I love to do things myself and save money so i might just rebuild for knowledge.