xconcepts

Ok I just replaced all of the pads on my wifes 08 RX350. Pretty straight forward as I have done other vehicles with no issue. I bought Akibono pads. However, I'm having a strange issue. I did not remove any brake fluid from the reservoir. If I'm sitting and pump the brake it obviously gets harder and harder to pump and they catch sooner. But if I'm driving I have to almost push the brake all the way to the floor to catch and slow down/stop. WHY!!!

The reservoir is above the max line.

diverchris

sounds like there is air in the brake line.

m1964

Did you open the cover on the reservoir? If not, you could have blown a seal in the master cylinder...
If you did not open the caliper drain screws and pushed old fluid back into to the MC, you also could have destroyed a seal in the MC...

xconcepts

I did not open the cover on the reservoir or the caliper drain screws. I still have braking pressure and capabilities just got to push in the brake more....I figured if I jacked up the MC then I wouldn't have any pressure.

m1964

the front and rear brakes have different "circuits" from MC, most likely only rear or front brakes work now properly-take it to a good mechanic, I guess you might need new MC.

Usually u have to open the cover on MC when doing the brakes, however in new vehicles its best to open caliper bleeders when pushing the pistons back in so the old fluid goes out, and not back into the MC-if the fluid was never changed, it may have small particlers that will damage seals in MC when you push old fluid back into MC.

Ask me how I know...did same thing but it was under warranty (it was not RX, but same rules apply)

mandyfig

If you did not have the brake issue with the old pads and seem to have a new issue after your brake work and did not even touch the fluid line, then maybe you just have an overflow issue.

When replacing pads, normally there’s a need to push back the pistons and therefore your fluid level will creep up. Hence some fluid needs to be take out before you start. It appears that you did not remove some fluid.

There’s a reason for the MAX and MIN level line on the fluid reservoir.

I suggest you remove fluid unto MAX level.

xconcepts

Apparently it worked itself out. I was gone for the weekend and she drove it with no problems. I drove it yesterday and it seems to be back to normal. I did remove some fluid to get it back to MAX level.

m1964

congratulations!