MattRX

One thing that always kind of bothered me a little with this car, is no matter what pads I run, there's a slightly vague and squishy feeling from the brakes. This is an "F-Sport", so I want it to feel sporty dammit! My 2008 RX350 really had this bad until I swapped to a 10" Camry brake booster and a more aggressive Advics master cylinder from a 2011-2016 Scion TC. And the parts were not defective, this is just how those older 04-09 RXs felt, I tried various ones (Japan-made and Canadian-made) and that is how they feel. That setup will get you German sports car-esque feedback. However, that exact master cylinder is not an option on these cars as these have opposing M12 x 1.0 ports vs. the tandem M10 ports on some of the older Toyota/Lexus cars, what IS possible is the booster though, I elected to just do the MC as the '08 RX is for fun.

Before going further, I'd like to mention that these modern Toyota MCs have no control whatsoever over brake bias, distribution or ABS/TRAC, it's strictly pumping fluid to the calipers, and they are all super strong and capable enough to run these dual pistons, whether it's an MC from a Corolla, or a Land Cruiser. The MC I went for was (PN: 47201-06443) from a 2012-2017 Camry or 2013-2018 Avalon. Physically on the bench, these MCs appear identical, but the inner springs are stiffer which provide a firmer and more abrupt pedal response. Piston stroke remains at 3" and it has two volume holes like the stock RX as well. Normally, I'd suggest getting one of these babies from a junkyard, but I couldn't find a Camry that new there, so I got it off eBay. They're available new from the MFR (Advics) themselves on Rockauto for about 100 bucks. PN is: ADVICS BMTU011 If you want to go further, the stock 10.5" brake booster can be substituted with a 10" one from a NA-made 2007-2011 Camry or 2008-2012 Avalon. Toyota was smart and kept the booster and MC fitment identical on most of their cars.

Now you won't be able to just bolt this Camry/Avalon MC on, you'll need to swap the reservoir to the correct one for a 3rd gen RX using a 3/16" or 5mm punch to pop out the pin. This annoying pin can be substituted for a M5-50mm bolt and locking hex nut. This reservoir itself can be salvaged from your original 3rd gen RX's master cylinder, or you can get it at a scrapyard from the following cars:
- 2010-2022 RX
- 2008-2019 Highlander
- 2011-2020 Sienna

You CANNOT use the reservoir from a 2nd gen (2004-2009) RX, it looks nearly the same, but the spacing is incorrect and slightly off, so it will not fit no matter what









Getting to the MC requires what would need to be done for a throttle body and MAF cleaning/service, so you may as well do that at the same time. Take out the battery, engine "beauty covers", 3 bolts for snorkel, air box and associated bits (I did not have to remove cowl). If you want to go one step further, that 10" Camry/Avalon booster will make the pedal firmer and provide more feedback. That's obviously a little more involved, but having done it on my 2008 RX350, I can definitely say it's worth it if you're a car guy who cares about the nit picks. You'd need a stubby 14mm wrench to adjust the booster and brake light switch. Reaching the brake light switch looks like a PAIN on these 3rd gens, so I opted out on the 10" booster for this car. The 07-11 NA Camry/Avy booster has the same 45mm adjustment and rod length as the RX, taking a bit of weight off the front end never hurt either. If anyone's crazy enough to attempt it, I'd love to hear about it!



Maintenance part list:

• 44785-02060 or 44785-0E020 (Brake booster good quality gasket - grab it with the brake booster itself)
• 44730-28030 (Upgraded metal brake booster check valve from ES350/Camry - there was a TSB for some Toyota/Lexus cars to swap to a metal valve to prevent dash rattles, not sure if this applies to 3rd gen though)
• 90480-24439 (Grommet for brake booster vacuum valve - grab if changing booster)
• 90029-15803 (Retaining pin for the master cylinder reservoir, I just used an M5-50mm hex bolt and nut instead)
• 90015-AH002 (Master cylinder to booster o-ring)
• 90029-48001 x2 (Master cylinder reservoir o-ring - (I didn't buy these as they were expensive and didn't seem to be needed)

carguy75

I just installed some PowerStop performance street pads for better braking performance and my 2015 RX350 have neck breaking initial grip when braking. Therefore, i would try upgrading the brake pads and rotors(high carbon) first.

Abrar

could you share the link

carguy75

Here is what I used for my brake upgrade on my 2015 RX350 AWD. I ordered the pads and rotors from Amazon. Warning: The Rx350 will not have smooth luxury like OEM braking with these. The stops are hard and rough like a performance model, but it will stop very well without brake fading.

MattRX

I tried a 2011 Sienna at work (Same entire brake system as our cars) with those Power Stop pads and rotors and it had a surprising amount of bite. Even more than my Raybestos EHT by a good amount. Makes me curious how they'd feel with the more aggressive master cylinder

carguy75

Well with the stock master cylinder the braking is pretty strong with the Power Stop pads/rotors, so I bet the RX350 will stop on a dime with the more aggressive master cylinder and Power Stop pads/rotors.

The stock rotor and pads does leave a lot to be desired in terms of braking feel if you are bit heavy footed. I assume that the stock master brake cylinder is a bit weak as well. For how I drive my RX350 the Power Stop brake upgrade works fine and feel more confident in the braking around town. My city driving requires some aggressive braking for the unexpected merges and sudden stops. I rather get rear ended than rear ending someone else.

Clutchless

I put Hawk LTS brake pads on the front of my Sienna which has as you said, the exact same brakes as the RX. I replaced OEM Toyota pads as they had terrible bite and with a full load the van just did not want to stop. With the LTS pads they grab right away and stop quickly. Much more confidene inspiring in heavy traffic and dealing with sudden stops, especially with a lot of stuff in the back. However Hawk only makes the front pads in this compound.

It appears the Hawks have a ferro-carbon compound and the Power Stop pads have a carbon-ceramic compound. I have the Raybestos EHT on the rear as Hawk does not make a rear pads. But now I may replace the rear pads with the Power Stop pads based on the above recommendations.
I have the Raybestos EHT on the RX and the Hawk pads are much much better at stopping faster. Still quiet and dust is not bad.
​​​​​​https://www.hawkperformance.com/lts

RX in NC

Wagner ThermoQuiet brake pads also have a great bite. They remain quiet as they wear and generate very little dust as well. I run them on all four of our vehicles. I usually order them from Rock Auto.

carguy75

Hawk LTS pads are great performing pads and last a long time. I used them on my old 2006 Cadillac Escalade and they stopped that big SUV on a dime without fading. I used Raybesto EHT as well and they stop very well too for the money.

Hawks LTS pad and Duralast high carbon rotors make a good combination.