Rear Disc Brake Theory

This has been a long awaited topic amongst all, as we’ve all pondered and wished we had rear disc brakes. Unfortunately, Toyota didn’t see the demand for them in our US market.

I’ve spent countless hours researching and I’ve discovered that Toyota developed parts that use similar bolt patterns for certain parts. So I’ve noticed there’s a pattern on some cars with regards to their rear brakes…thus having the potential to have brakes interchangeable.

I have come to the conclusion that the following two setups will fit the rear of the RAV4.1’s in the US. I’d just like to note, since I’ve sold my RAV4 I can’t confirm these setups with work, it’s truly up to another brave RAV4 owner to give it a go!

The most difficult part of both setups is acquiring the back plate which is how it all comes together. These back plates are expensive from the dealer and can cost upwards of $300. The easiest way to do this is to swing by a local wrecker or junkyard and buy them there…make sure they are complete with the entire brake assembly.

Here’s what you’ll need:

– Backing Plates
– Drum Parking Brake Assemblies
– Drum Brake Pads
– Rotors
– Brake Pads
– Brake Shims
– Brake Calipers
– Brake Calipers Brackets
– Parking Brake Cables (may not need them as stock cable compatibility has not been confirm)

The first setup comes from our beloved family minivan, the Toyota Sienna specific the 3rd generation Sienna. While I unraveled these I discovered this setup is used on the rear of other Toyota and Lexus models:

TOYOTA SIENNA 2011-2015

TOYOTA HIGHLANDER 2014-2015

LEXUS RX350 2010-2015

LEXUS RX450H 2010-2015

Here’s a few photos of the major parts you’ll need with specs.

backingplate2 backingplate

2012siennarotors 2012siennacalipers 2012siennapads

Backing Plate Part Numbers:

LEFT REAR BACKING PLATE 46504-08020

RIGHT REAR BACKING PLATE 46503-08020

Caliper Bracket Part Numbers:

LEFT REAR BRACKET 47822-0E020

RIGHT REAR BRACKET 47821-0E020

Caliper Part Numbers:

LEFT REAR CALIPER 47830-0E020

RIGHT REAR CALIPER 47850-0E020

 

The second setup comes exclusively from theToyota Rav4.2 or simply the 2nd generation Rav4. These are a bit harder to find do them being a less common option and less of them on the road. Note these setup does not require a brake caliper bracket as it was design to have less parts.

TOYOTA RAV4 2001-2005

rav4.2rotors rav4.2calipersrav4.2pads

Backing Plate Part Numbers:

LEFT REAR BACKING PLATE 46504-42021

RIGHT REAR BACKING PLATE 46503-42021

Caliper Setup Part Numbers:

LEFT REAR CALIPER 47750-42050

RIGHT REAR CALIPER 47730-42050

And if you don’t this is possible just check out our Rav4 friend in Russia

http://www.drive2.ru/cars/toyota/rav4/rav4_i/gte-starichok/journal/178490/#post

I have a partial Sienna setup for sale if anyone is interested…just shoot me an email or comment. To be continued….

 

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GOING ONCE, GOING TWICE – Any takers?

It pains me to write this but up for sale is my beloved ’96 Toyota RAV4. This is no ordinary RAV4, its rare, unique and more of an enthusiast car then your typical grocery getter. It’s been modified to receive a ST215 Toyota Caldina 3SGTE engine and its E150F transmission. It’s AWD, has dual sunroofs, power accessaries, working AC as well as some more goodies!!

Check my eBay auction at:

RAV4 GTT EBAY AUCTION

IMG_5826

If you’re interested contact me at scubastevoviii@aol.com. 

Front Brake Theory Pt. 2.5 – Stage 1 Brake Upgrade

I’d like to revisit my posts on brakes, as some questions have surfaced and I’d like to help answer them. For some people out there, my brake setup is not ideal because it requires some grinding for fitment and wheels spacers to use 16inch wheels…so, how does one still upgrade without having to do all that?

Well, good news is you still can upgrade from your stock setup still use your stock 16inch wheels. I haven’t had the funds or time to experiment with this and I can’t make an promises but I have a pretty good feeling this new setup will work.

Here is the Stage 1 Brake Upgrade:

Brake Caliper with Bracket – Celica ST (95-99)

Part Numbers:

RH 47721-20370 or 47721-20371

LH 47722-20080 or 47722-20081

stcelicabrakecaliper1stcelicabrakecaliper5

Rotors – Lexus RX300 (99-03)

Part Number: 43512-48011 or 43512-48060

rx300brakerotorrx300brakerotor1

 

Pads – Celica ST (95-99)

Part Number: 04465-20140 or 04465-33021

stcelicabrakepads

I can’t confirm any modifications will be needed but if it does, it will be less then my Stage 2 Brake Upgrade. This setup will feel and work just fine with the stock brake master cylinder.

Master Cylinder Selection

After using my upgraded brake setup for over 2 years now, I’ve begu to research again and source farther potential upgrades. As I mentioned previously, this particular setup increased pedal travel and I had recommended using a larger brake master cylinder. This is of course if you don’t like how the brakes feel. I’d like to state its not necessary as the stock master cylinder has been tested to work for more then 2 years…especially if you’re working with a tight budget, which most of us are.If have to ask yourself, that type of pedal feel do you want and how do you want the brakes to response. Now with that said here’s what I’ve gathered so far.

I always like to begin with a reference diagram of the original parts (brake master cylinder circled in red):

sxa10stockmr2toyotadiagram

The stock Rav4 brake master cylinder has a inner bore of 7/8″ inches. NOTE – I circled the front brake line outlet as this became a vital sourcing a direct bolt on upgrade.

sxa10mc3 sxa10mc2 sxa10mc1

There are two master cylinder upgraded there are direct bolts on’s…

Subject A

The ST204 1994-1999 Toyota Celica with a bore size of 15/16″ inches.

OEM Part Number # 47201-2B090

st204mc3st204mc2st204mc1

Subject B:

The MCU10 1999-2000 Lexus RX300 with a bore size of 1″ inch.

OEM Part # 47201-48030

rx300mc3rx300mc2rx300mc1

A little general advice about selecting bore size in your master cylinder may be helpful… Decreasing MC bore size will decrease your pedal effort and increase your pedal travel. Conversely, a larger bore in your car’s master cylinder will, all other components being consistent, increase your pedal effort and decrease your pedal travel. As with some other brake parts purchases, this comes down to your preference for how the brakes “feel” under foot when you are driving.

To complete this master cylinder swap, you’ll simply have to use the Rav4 brake fluid reservoir with new seals, bolt it all up, pour some fresh fluid and bleed the brakes.

Front Brake Theory Part 2 – Stage 2 Brake Upgrade

Welcome to part 2 of my Front Brake Theory! I left off with alot of material from my first post…some of you have messaged me about a follow-up. I have to apologize for a late response. Since, I have selected my setup and have been testing it for over 4 months.

DISCLAIMER/WARNING: This is simply a guide, written to be and is intended as informational tips. This is not a 100% accurate or guaranteed foolproof guide. Work on your own vehicle at your own risk. If after reading through these tips, you do not feel comfortable doing the work yourself, please seek the help of a professional mechanic. I cannot be held accountable for your safety or vehicle. I do not take any responsibility for any damage to personal property or injury to yourself.

Here is the Stage 2 Brake Upgrade:

I’ve selected: Brake Bracket – Celica GT (95-99)

Part Numbers:

RH 47721-20420

LH 47722-20120

 96celicafrontbrakebracket3a 96celicafrontbrakebracket396celicafrontbrakebracket1

Rotors – Lexus LS430 (01 – 06)

Part Number: 43512-50220

Ls430rotorCalipers – Toyota Avalon (95-97)

Part Number:

RH 47730-07020

LH 47750-07020

avalon96frontcaliper avaloncalipers

Pads – Toyota MR2 Turbo (92-95)

Part Number: 04465-17060

Here are some reference shots: Rotor Comparison…Lexus LS430 (01 – 06) on the left and the Rav4 (96-00) on the right. IMG_8925 Test Fitting…the Celica GT (95-99) Brake Bracket. The dust shield was bent slightly to accommodate the larger 315mm diameter rotor. IMG_8924 More Test Fitting…the Celica GT (95-99) Brake Pads (these were too thick to seat properly into the brake pads clips). IMG_8928 Here is the caliper mounted and the complete what I’ll call “prototype” version of this setup.

IMG_8930IMG_8976

Fitment

There are few spots on the Celica Brake Bracket that need to be grinded to support the (1)thicker rotor, (2)the larger diameter as well as (3)the offset of the rotor. The newer setup will not work with the stock 16 inch wheels unless you use a wheel spacer (25mm thick)…I’m using the H&R one on my stock 16 inch wheels and it barely fits. Its probably better to use the Celica GT caliper over the Avalon calipers because the master cylinder will work much better with the single piston setup. I need to install a larger one with my setup, which means more $$ …which is what I was trying to avoid.

Driving Impressions

It’s a tight fit that will create a front brake bias (with the twin piston calipers) but works with no brake fade unlike that stock setup. Since I did not change/upgrade the master cylinder, the pedal travel has increased…while its good for pedal modulation, its in need of a larger bored cylinder due to the larger hydraulic volume in each caliper. Brake fade resistance has definitely improved. I plan on upgrading the rear brakes, changing the master cylinder and adding some stainless steel brake lines. Good luck, drive safely, and have fun!

Front Brake Theory Part 1

As I began planning a full-scale assault of upgrades, I’ve approached a huge problem…the front brakes!  While the stock front setup uses a 302mm  diameter rotor, which isn’t too bad, they’re ONLY 18mm thick. After a few seconds of hard braking these things cook…can you say brake fade. They get so hot, so fast, and retain all that heat…they’re pretty much useless. There’s nothing worse then thinking you can’t stop and then you have to get all Fred Flintstone on your floorboard. Ok…that’s a little extreme, but you get the point. I needed to figure out an affordable solution.

On the other side of things, the Rav4 uses a single 54mm piston caliper. While this is adequate for the stock setup, its marginally enough to shut down 250-300ft/lbs of torque. To say the least, a front brake upgrade is a MUST have for my Rav4 GT-T.

Where do we begin…

Here are the stock specs of the Rav4.1 front brakes:

***Brackets & Pads***

Here’s something truly insightful…Toyota has managed to design, an almost universal brake caliper system. They use a standard brake caliper bolt pattern, a 160mm between a wide range of caliper sizes. They’ve also created a standard brake pad size amongst the range as well. Combined, these give Toyota an incredible amount of flexibility throughout the entire Toyota/Lexus/Scion fleet. This also shows, just one way, how Toyota has been successful over the years. I’ve digressed…back to the subject at hand.

I had to start by searching for another caliper bracket that fits the Rav4 steering knuckle and supports the use of a thicker rotor (more then 18mm). So went back to a thread on Rav4World…where a member stated that the ST206 (Toyota Curren) brake caliper bracket shared the same bolt dimension as the Rav4 steering knuckle. Now WTH is a Toyota Curren (scratches head, rises eyebrow)…it’s basically a 94-99 Celica (ST202) chassis with a different body. With that said, it turns out that ST202 Celica steering knuckle has the same bracket-to-knuckle bolt pattern as the Rav4.1…130mm.

Now here in the US, the ST202 or 6th Gen Celica as some prefer, has two different brake setup: ST (base) & GT (sport). The ST caliper & bracket supports a 25mm thick rotor while the GT caliper & bracket support a 28mm thick rotor. Next up was finding out what pads fit each bracket.

ST setup

Here a list of Toyota’s that use the same ST pads:

GEO PRIZM (1993 – 1997)
TOYOTA CAMRY (1992 – 2001)
TOYOTA CELICA (1994 – 1997)
TOYOTA COROLLA (1993 – 1997)
TOYOTA RAV4 (1996 – 2003)

As you can see, the ST pads are exactly same as the stock Rav4 pads.

GT setup

Here a list of Toyota’s that use the same GT pads:

LEXUS ES300 (1992 – 1996)
LEXUS LS400 (1990 – 1992)
LEXUS SC300 (1992 – 1998)
TOYOTA AVALON (1995 – 2004)
TOYOTA CAMRY (1992 – 2001)
TOYOTA CELICA (1994 – 1999)
TOYOTA SIENNA (1998 – 2003)

The GT uses a larger pad design. Also note the larger bracket attached the caliper, this will provide the use of a ~20mm taller diameter rotor then the ST setup.

***CALIPERS***

Now I could just stop here and use either ST or GT calipers, as they both use a 57mm piston….OR I could go on and look into other potential candidates…I opted for the latter. I started to look for other non-ST202 Toyota calipers. The stock Rav4 caliper piston is 54mm, which is the same as the Corolla. If I want an upgraded setup, I needed to focus on the larger piston setups from bigger and heavier models. The concept here is, larger the piston, the more surface area…the more surface area, the more clamping force they’ll have on the rotor…the more clamping force to shut down the ~250-300hp.

The candidates:

TOYOTA SIENNA (1998 – 2000)

TOYOTA SIENNA (2001 – 2003)

LEXUS LS400 1990

TOYOTA MR2 (1992 – 1995)

LEXUS ES300 (1994 – 1996)
TOYOTA AVALON (1995 – 1997)
TOYOTA CAMRY (1994 – 1996)


LEXUS IS300 (2001 – 2005)


LEXUS SC300 (1992 – 1998)

LEXUS SC300 (1999 – 2000)
LEXUS SC400 (1992 – 2000)
TOYOTA SUPRA (1993 – 1998)

***ROTORS***

I then needed to figure out how large of a diameter rotor I would need with each corresponding pad, caliper & bracket combo. It’s important to note, you’ll need a rotor that has a 62mm hub bore and a 5×114.3 lug pattern.

Here is a list of models with matching front brake rotors :

LEXUS ES300 2003
LEXUS ES330 (2004 – 2006)
LEXUS RX300 (1999 – 2003)
TOYOTA CAMRY (2002 – 2004)
TOYOTA HIGHLANDER (2001 – 2007)

LEXUS LS400 (1995 – 2000)

LEXUS LS430 (2001 – 2006)

LEXUS RX330 (2004 – 2006)
LEXUS RX350 (2007 – 2009)
LEXUS RX400H (2006 – 2008)
TOYOTA HIGHLANDER (2006 – 2007)

TOYOTA SUPRA (1993 – 1998)

TOYOTA VENZA (2009 – 2010)

LEXUS RX350 2010
TOYOTA HIGHLANDER (2008 – 2010)

LEXUS GS350 (2007 – 2009)
LEXUS GS430 (2006 – 2007)
LEXUS GS460 (2008 – 2009)
LEXUS IS350 (2006 – 2010)

This theory laid out the foundation for my new Rav4 GTT brake setup.

LET’S RECAP

My focus is to reduce brake fade after repeated hard braking and increase the brake’s thermal capacity. So by increasing the thickness, the brakes can absorb and dissipate more heat then the stock setup and work more consistently under grueling conditions.

Another part has been increasing the rotor diameter. There a simple rule: the larger diameter of the rotor, the more force that is available to stop a wheel…kinda like using a longer wrench. It gives you the leverage and makes it easier to break a frozen bolt loose. Now in theory, if I kept the same caliper and same pads, but installed a larger diameter rotor, you would have greater stopping power. Even, a reasonably larger diameter rotor will provide increased stopping power.

The 3rd area of interest is # of pistons. The dual-piston caliper has several advantages over its single piston counterpart. The most obvious advantage is that with increased piston surface area. With increased piston area, the caliper is able to generate more torque. More torque means more stopping power with an more even pressure distribution over the pads. The more even the pressure is on the pads, the smaller the risk of the pads chattering and the better brake control you’ll have.

Of course lastly, bigger brakes without better tires and a better suspension set up to take advantage of them are pointless…stay tuned!