draco

Has anyone done this? If so, does anyone have a procedure on how to do this on a 2004 RX330?

kiwi

the best way to do this is to adjust the parking brake at the rear. you will need to remove the rear wheels. on the backing plate there should be a rubber plug, you will need to pop that off and insert and adjusting tool, normally a flat head screw driver will work fine, you will need to use the tool to turn a star shaped adjuster, this will increase/decrease the space between the shoe and the drum (insde portion of the disc).

a brake service at the dealer will cover this,.

salimshah

Disclaimer ... I dont have RX330 so my comments here are based on my RX300 and Sc400 and GS400 [good gamut of Lexus]. Also you mentioned foot brake ... both the brakes are operated by foot .. I am assuming you are talking about the aux-brake/parking brake.

There is a pawl which automatically adjusts the shoe [it is a drum brake]. It should work till the shoe runs out of lining or there is a problem with the mechanism.

For auto adjustment to work you apply the foot brake and release it repeatedly. Some time it helps if the wheel is turning.

You can open it the drum up and inspect, but I would still suggest that you use the auto-adjust to raise the shoes. If you under-set the cog (exposed through the rubber hole [oh you need to spin the hub/hole to match with the static brake mechanism]) you will be using the auto-adjust to raise it. If you over set the cog, then you get drag and the brake shoe will burn.

So why the cog ... well it is the piece that gets ratcheted by the pawl for auto-adjust, and you need to turn it down if the shoes have cut a path in the drum. A good mechanic initially sets it so that the drum can go on and minimum time is spent doing auto-adjust ... one or two cogs per auto-adjust and a full turn may need 50+ auto-adjust actions.

Keep in mind the brake assembly is floating and you need to make sure it is centered ... with the drum on, use rubber mallet to strike the drum at various spots as you spin it.

The drum may not cooperate if you plan to remove it. Post here is you get stuck. The setup is spring loaded (has locks) but if you try to disassemble it can quickly be in pieces ... need to know what you are doing.

Salim

JERKRICE

Yes salimshah , I think my brakes are to soft when press should ...i try and adjustment them ?

thanks

RX330inFL

You do not mention which RX you have, however, if I were to guess I would first check your brake fluid levels. As the pads wear there is more room in the system for fluid which it takes from the reservoir lowering its level. Something to keep an eye on over the length of your brake lifespan. Something the dealer is supposed to check at each 5K service and top off as needed.

As for the brakes themselves, they are self adjusting. Only the parking brake has any real adjustment to it.

If the fluid level is where it should be and the pads are within spec, I would see about bleeding the brake system to get out any possible air in the system.

rbh2000

Here is the CORRECT info from the Chilton RX 330 Repair Manual #68354 from page 9-19 Parking Brake Adjustment.
1) Slowly depress the parking brake pedal all the way and count the number of clicks. It should take about five to seven clicks to apply the parking brake. If it travels less than five clicks, there is a chance the parking brake might not be releasing completely. If it travels more than seven clicks, the parking brake may not hold adequately on an incline, allowing the car to roll.

2) Release the pedal.

3) On 2004 and later models, the parking brake adjustment is performed at the pedal assembly.

4) Loosen the locknut and tighten or loosen the adjuster nut. Tighten the locknut after the desired travel is attained.

This locknut is located directly at the top of the pedal by looking up. This nut will be facing down at the top of the foot pedal.
Sorry for not posting the picture, but it is on page 9-19

You will not need to mess with the self adjusters located at the rear wheels as they are self adjusting.

Hope this helps bob

rcy

The original thread is from 2010 and Salimshah and I have since argued the point about the automatic adjuster. I should point out that there is no automatic adjustment on the drum parking brake built into the rotor disc as there is on a regular drum brake. They need to be manually adjusted. There are two adjustment points - one is the adjuster at each rear brake, and the other is the adjuster at the parking brake pedal. The adjusters at the brakes account for pad wear - the adjuster at the pedal accounts for cable stretch.

I would adjust the rear via the star wheel (inside the disc after you remove the rubber plug on the rotor 'hat' - the rubber plug should be approximately at the 6 o'clock position) until the pads are just grabbing the rotors, then back the star wheel off slightly until there is no drag. Then check the # of pedal clicks and adjust that via the nut adjuster at the pedal.

Lexterious

This is an old thread but having just done a parking brake adjustment on my 2004 RX330, I can say that this post is only partially correct.

1) the cable adjustment at the pedal assembly can only compensate so far. If the actual mechanism at the rear rotors is too far out of adjustment or parts are worn, this won't fully fix the situation.
2) the comment about not needing to mess with the self-adjusters at the rear wheels is incorrect. There is no self-adjusting mechanism on the 04 RX330 parking brake system. It's mostly similar to a standard drum brake system but it has no self-adjuster.

Lexterious

As mentioned in my post above, I just did this procedure on my 2004 RX330 and @rcy 's post is correct.

Some minor corrections based on my experience:

1) the 6 o'clock position is close. I've found it to be more like "6:30". This assumes that someone has installed the brake rotor so that the adjustment hold lines up with one of the big holes on the wheel hub. The rotor can go on in one of 5 orientations and I think only 3 are correct.
2) the following is really just my advice (I'm not a pro) and you can take it or leave it.

By the time your parking brake needs a fair amount of adjustment, it is likely that it needs to be serviced. And by this, I mean that it should be cleaned and lubricated regardless of whether or not there is sufficient pad thickness left in the brake shoes. This is because there really is no pad wear because you are using not using the parking brake to stop the car. Therefore if your pedal travel is going long, it could be other factors that could be fixed by servicing the mechanism.

In my case, last year, due possibly to Covid-related inactivity (we didn't drive the car for quite a few months), the mechanism fully seized up, rusted to the drum, the car couldn't move very easily as the parking brake was "always on" (the parking brake pedal had a funny feel too).

I had to take it apart, install a new set of hardware (springs and other fiddly pieces), and then clean and lubricate everything.

Further, due to the susceptibility of the rear parking brakes to seizing up due to rust and/or dirt, I am scheduling such a brake maintenance every Spring with my changeover from winter to summer tires. I recommend others consider doing the same.

It's a dirty ugly and fiddly job but should be doable within 2 hours (which also includes servicing, cleaning, and cleaning the rear calipers and brake pads, which is also a good thing to do (as is doing the same to the front brake mechanism... so plan on 3-4 hours on a warm Spring day).