AfterMarketNews AfterMarketNews Auto Care Pro AutoCareCareerHub Brake&Frontend BodyShopBusiness Counterman EngineBuilder Fleet Equipment ImportCar Motorcycle & Powersports News Servicio Automotriz Shop Owner Tire Review Tech Shop Tomorrow's Tech Underhood Service Speedville

Google Your Shop - What Do You See?

Go and enter the name of your shop at Google.com. Try putting quote marks around the name of your shop, like “Main Street Auto Care.” Now try entering the city where you are located with the name of your shop. What did you find? Your shop’s website?...

Read more...

Tennessee Shop Offers Discounts To Customers In Need

Price is often the biggest sticking point in an auto repair job. Some customers just have no feel for what certain services or parts cost, others have perhaps been treated poorly in the past (or are cheap), and some just flat out do not have the money....

Read more...

Technicians Are Modern-Day 'Code Talkers'

During World War II, the U.S. enlisted the help of Navajo and Comanche Native Americans as radio operators to use a code involving their language to disguise the real message over unsecured radio waves. If they were going to say the word “army,”...

Read more...

Vehicle Unit Increase; Import-Rich VIO Are A Boon for Import Specialists

Need a dose of good news for your business? Then hear this: The influx of new vehicles in the market will lay the foundation for bountiful aftermarket service and repair opportunities. And, with import vehicle sales continuing an ­upward climb, there...

Read more...

Honda: Engine Shuts Off, But Power Mode Stays In ‘On’ or ‘Accessory’

Applies To: Honda Insight models with one-push start Customers might complain that when they shift into park and shut off the engine, that the power mode stays in On or Accessory. Honda says the culprit could be a misadjusted shift cable. If the...

Read more...

Import Oil Specification Primer

As engine technology has evolved and fuel efficiency standards have tightened, oil specs have increased in importance. Using the wrong viscosity could set a fault code in some applications or interfere with the normal operation of the variable valve...

Read more...

2015 Vehicle Lifting Points Guide Now Available

The Automotive Lift Institute, Inc. (ALI) announces the availability of the 2015 edition of ALI’s “Vehicle Lifting Points for Frame Engaging Lifts.” This updated guide is a quick-reference single-source manual for lifting point information as...

Read more...

Pulling Codes: P0302: Cylinder 2 Misfire Detected Intermittent Activity

  This article will address a misfire code from a different vantage point. It will look at a plan of attack for when a code is being set intermittently. The code we are referencing is P0302-Cylinder No. 2 Misfire Activity Detected. While...

Read more...

Registration Now Open For ToolTech 2015

The Equipment & Tool Institute (ETI) is hosting its ToolTech 2015 event April 13-16 at the Radisson Hotel and Suites in Downtown Austin, Texas. This year's theme is "The Connected Vehicle: Opportunities and Challenges." Information and technology...

Read more...

Solving Carbon Deposits In Direct Fuel Injection Engines

Symptom: Misfire codes, stumbling and suspicious fuel trim numbers. On a scan tool, the engine may show a loss in volumetric efficiency. The driver may complain about a loss of power, poor fuel economy and hard starts. Cause: Carbon deposits on...

Read more...

Selling the Complete Serpentine Belt Job

Technicians and customers have pretty much accepted that the accessory serpentine drive belt should be replaced between 90,000 to 100,000 miles. It is a “slam dunk” sale to just replace the belt, but does that replacement belt have the same chance...

Read more...

Gasket Guide: Match A Sealant With Every Type of Gasket

Cork/Composite Gaskets Sealants: Cork and composite gaskets can seal a variety of underhood applications from valve covers to carburetors. The type of sealant used with these gaskets depends on a variety of factors. First, you must consider if the...

Read more...

Home Brake Job BRAKE JOB: Toyota Tundra Brake Caliper Upgrade

Print Print Email Email

For the Tundra line (including the ­Sequoia), the main miscalculation was in the brakes. Someone forgot to inform the ­engineers that American pickup trucks get overloaded and driven hard on a regular basis. As a ­result, the early models of the Tundra and Sequoia suffered from moderate to severe brake ­pulsation.

At first, most customers and repair facilities just ­regarded this as a normal brake problem, but it soon ­became obvious that the brakes were not up to the hard use customers were putting the trucks through. An upgrade was engineered and information was provided through a service advisory, as production changes added a larger caliper system in front and disc brakes in the rear to substantially improve braking performance, while reducing the incidence of pulsation complaints. This upgrade became the standard brake ­system on late 2005 truck models.

Though some of these trucks were updated under warranty, others have been transferred to new ­owners and the problems show up again as these new owners subject them to heavier-duty use. That’s where this update becomes an opportunity for independent ­repair shops to educate and earn the trust of owners of these vehicles.

In this article, I’ll highlight the procedure we’ve used to update the front brakes while shaving ­expense and procedures to lower the cost and the time required to perform the upgrade, yet still providing all of the benefits of the later-type brakes.
The reason this is such a problem is due to the very nature of the brake system used on these trucks. For years, the standard Toyota truck brake type was a fixed caliper with dual inner and outer pistons. By design, this type of caliper cannot tolerate even a small amount of runout in the rotor or hub, or looseness in the wheel bearing. Any deviation as the rotor turns is transferred directly through the hydraulic system to the pedal.

Diagnostics
If a 2000-’05 Tundra or Sequoia comes into your shop with a complaint of brake pulsation, there are a few diagnostic steps that should first be taken before ­repairs are recommended.

Are the front brakes causing the pulsation, or are the rear? The only way to know for sure is to test drive the truck and get a feel for the severity of the problem. This will also eliminate the possibility that the customer is feeling the ABS when braking on slippery roads, and not a mechanical problem. Tire condition, balance and alignment faults can also cause braking problems that may need attention to make a full repair possible. Braking with light and heavy ­application and use of the park brake on models with rear drums will help isolate the source of the vibration. We’ve updated the front brakes on a number of these trucks, only to find that there is also pulsation from out-of-round drums in the rear.

figure 1: the upgraded toyota tundra caliper holds a larger brake pad.A visual inspection of the brakes on the particular vehicle is the next step. The Toyota service bulletin #BR001-03 REV gives a pictorial view of the two different types of calipers used on these vehicles. The mechanical difference boils down to the updated caliper being much larger to hold a larger pad. The difference between the two styles is obvious when they are seen together (See Figure  1), but can be a little hard to distinguish individually.

The easy way in this case is to measure the size (width) of the brake pad (See figure  2). The early style pad will be less than 5” (4-11/16” or 199.5 mm) in width; the later update is more than 5” (5-5/16” or 231 mm). Both of the calipers have the same dimensions on the mounting bosses.figure 2: the upgrade toyota tundra brake caliper adds more than 30mm of length to the brake pad.

Once it’s been determined that the truck is a candidate for the update, a look at Toyota bulletin #BR004-02 REV will provide reference numbers for parts that you may need.

But read through this article first. The update will replace the calipers with a larger set that will provide additional swept area and fluid capacity for heavy-duty use. The service bulletin gives a very complex and involved procedure for changing the components that’s just not necessary to get the benefits of the update.

In our shop, we’ve done this upgrade a number of times with mixed results and have come to some conclusions about how the repairs and upgrades should be done, with the least possibility of a comeback. Even after the upgrade, some customers may exceed the loading and use recommendations that these ­vehicles were designed for. That may require a heart-to-heart talk with the customer regarding the intended use of the vehicle, and its limitations.

If you get a vehicle in that ­already has the upgrade, but still has pulsation problems and no indication that the vehicle is being abused, additional diagnosis may be needed to get to the root cause of the problem.

Caliper Upgrade
The TSB mentioned earlier involves replacing a number of components in the front brakes. The calipers are changed only after removing the axle, wheel hub, wheel bearing and other attached parts, such as the ABS sensor and shock absorber. ­Although the listed warranty time is sufficient for the repairs, the chances of damaging the wheel hub and the cost of a new bearing adds time and dollars to the upgrade.

Following are the procedures we use, and the reasons why this is a better approach to the brake upgrade, saving time and dollars. The factory procedure is a good, complete upgrade, but as noted above, it may not totally resolve brake pulsation on all vehicles. The procedure we use gains all of the benefits of doing the job as directed in the TSB, but eliminates steps that add time and cost.  
1. After the road test, allow the brakes to cool. Look for obvious signs of a bent wheel, missing wheel weights or obstructions that might cause the wheel to not seat properly on the hub.

2. Disconnect the brake line from the caliper and use a container to catch the fluid. Since the caliper is being replaced, there is no reason to retract the pistons or push the old fluid back into the system.

3. Remove the caliper, complete with pads and hardware. Remove the brake disc.

4. Clean the mounting surface of the wheel hub. Use a dial indicator to check runout on the hub. There should be ­almost no runout at the hub-to-rotor mounting surface. If the hub runout is good, do not remove the axle nut or any other parts as listed in the bulletin; this is where you save money and time. The only reason the factory bulletin has you remove the bearing housing, hub and wheel bearing is so the dust shield can be changed to one with a larger cut out for the larger caliper.

Figure 3: To fit the larger brake caliper, it is necessary to trim the backing plate/dust shield.5. Hold the replacement caliper in place, lined up with the mounting bosses, and scribe or paint a line on the backing plate (dust shield) that will provide the added clearance needed for the new caliper (See Figure 3). By the way, rebuilt calipers are available from a number of sources in both the old and new types. New calipers do not have to be used for the upgrade.

Use your metal cutting tool (my preference is an air-powered reciprocating saw) to cut out the backing plate to accommodate the caliper. Round off any sharp edges and spray a little rust preventive paint on any bare metal.  

6. Mount a new rotor to the hub, check for runout on the normal pad surface (maximum allowable runout is 0.03 mm or 0.0012 in.) and install the upgraded caliper. The mounting bosses on the new caliper are slightly thinner than the originals, so a new set of mounting bolts (listed in the bulletin) are recommended unless you want to spend the time grinding on the old ones.  Though not absolutely necessary, replacing the metal fluid lines to the calipers, rather than rebending the old ones, makes a better repair. Be sure to follow the torque specs in the TSB.

7. If the replacement calipers did not come with pads, use an OE-quality replacement. You will need new hardware if it’s not supplied with the calipers.

8. Fill the brake fluid reservoir with fresh fluid and bleed the system. Reinstall the wheels using the proper tightening sequence and torque. Set tire pressures and adjust the rear brakes.

9. The road-test and break-in procedures are critical to the completion and success of this repair/upgrade. Take the time to follow the pad manufacturers’ recommended break-in steps, and then drive the vehicle on a normal test-drive to verify that the pulsation is gone.
    
 

The following two tabs change content below.
Latest articles from our other sites:

Vehicle Unit Increase; Import-Rich VIO Are A Boon for Import Specialists

Need a dose of good news for your business? Then hear this: The influx of new vehicles in the market will lay the foundation for bountiful aftermarket service and repair opportunities. And, with import...More

ShowMeTheParts-Mobile Has Been Optimized For Faster Paging

ShowMeTheParts-Mobile has been optimized with faster paging for mobile phones and tablet devices, giving users an improved experience. In addition, branded versions developed for the company's manufacturer...More

Vehicle Unit Increase; Import-Rich VIO Are A Boon for Import Specialists

Need a dose of good news for your business? Then hear this: The influx of new vehicles in the market will lay the foundation for bountiful aftermarket service and repair opportunities. And, with import...More

Honda: Engine Shuts Off, But Power Mode Stays In ‘On’ or ‘Accessory’

Applies To: Honda Insight models with one-push start Customers might complain that when they shift into park and shut off the engine, that the power mode stays in On or Accessory. Honda says the culprit...More

2015 Vehicle Lifting Points Guide Now Available

The Automotive Lift Institute, Inc. (ALI) announces the availability of the 2015 edition of ALI’s “Vehicle Lifting Points for Frame Engaging Lifts.” This updated guide is a quick-reference single-source...More

Pulling Codes: P0302: Cylinder 2 Misfire Detected Intermittent Activity

  This article will address a misfire code from a different vantage point. It will look at a plan of attack for when a code is being set intermittently. The code we are referencing is P0302-Cylinder...More

Solving Carbon Deposits In Direct Fuel Injection Engines

Symptom: Misfire codes, stumbling and suspicious fuel trim numbers. On a scan tool, the engine may show a loss in volumetric efficiency. The driver may complain about a loss of power, poor fuel economy...More

Selling the Complete Serpentine Belt Job

Technicians and customers have pretty much accepted that the accessory serpentine drive belt should be replaced between 90,000 to 100,000 miles. It is a “slam dunk” sale to just replace the belt,...More