Archives August 2024

Blue Bird Corporation announced it has delivered its 2,000^th electric, zero-emission school bus, which it said marks “an industry-leading milestone.” Clark County School District (CCSD) in Nevada received Blue Bird’s 2,000^th electric vehicle (EV) to help the nation’s fifth largest school district transition its school bus fleet to clean student transportation.

CCSD operates 373 schools serving more than 300,000 students. The district maintains a bus fleet of more than 1,900 vehicles. CCSD transports over 123,000 students each school day on more than 1,400 bus routes.

Blue Bird said it provided its most advanced All-American electric school bus to CCSD. Featuring Blue Bird’s new, extended range battery, CCSD’s milestone zero-emission vehicle can carry 84 students. Depending on the charging infrastructure, the bus takes between three and eight hours to recharge fully.

CCSD received a $9.875 million grant through the U.S. Environmental Protection Agency’s (EPA) Clean School Bus Program to purchase electric school buses, including Blue Bird’s zero-emission milestone unit. This program is part of the Bipartisan Infrastructure Law (BIL) which provides a total of $5 billion over five years for clean school bus transportation nationwide.

CCSD’s milestone unit is now one of more than 2,000 Blue Bird electric school buses serving school districts across 41 U.S. states and 4 Canadian provinces, according to Blue Bird. Replacing 2,000 diesel-powered and polluting school buses with an equal number of zero-emission vehicles reduces harmful carbon emissions by more than 21,000 metric tons annually. In addition, nearly 150,000 students a day are no longer exposed to diesel tailpipe emissions linked to serious health issues such as asthma or heart disease, the company added.

On racecars, mechanics in the pit lane will tune the settings of the shocks and springs for the track. Some race shocks have six adjustments for compression and rebound, so they can be tuned for the exact amount and rate of suspension movement needed. But the moment they leave pit lane, the settings can’t be changed.

Electronically adjustable shocks and struts have been available for 20 years. The first applications were on luxury and sports cars, and the different modes could only be selected by the driver. These early systems firmed up the compression and rebound settings. The units typically had a small stepper motor mounted on the shaft of the strut or shock that went down into the valves of the piston or into the base of the unit.

Modern systems can read the road and the driver’s intentions to help select the correct amount of dampening force. These systems see the vehicle dynamics through accelerometers and Hall-effect sensors, and they can change settings in milliseconds. Some can even detect potholes and dial up the rebound so the wheel does not drop to the bottom.

Electronic Shocks/Struts

Electronically adjustable shocks and struts use conventional mono-tube and twin-tube oil-filled dampeners. The rods, gas chambers and piston have the construction of passive units. Like a passive unit, they can fail if they leak, the gas escapes or the rod is bent. They can also wear out like a conventional unit as the oil inside breaks down and surfaces in the bore wear.

What make these units unique are the valves with their variable orifices. These valves regulate the flow between the chambers on either side of the piston. The piston in some units, however, does not have any valving.

The size of the orifices is controlled by electromagnetic solenoids that can control the valves very quickly. The electrical connections and solenoids are typically found outside the body and act on the valves inside the unit using magnetism. The signal to the solenoid is pulse-width modulated and varies the voltage to change the size of the orifice.

The valves and solenoids can’t be serviced or separated from the shock or strut. If a problem is detected with the system, the valves go into a fail-safe position that is fixed, and the system becomes passive. The driver is then alerted to the problem with a message or light on the instrument cluster or message center.

Measuring Wheel Movement

Ride-height sensors not only measure the position of the suspension, but also the rate of movement. They are supplied with a voltage of around 5 volts. The signal voltage is changed as a magnet moves past a coil. Most sensors have three wires — ground, power and signal.

Internally, it is difficult to damage one of these sensors. Externally, the linkage that connects the sensor to the suspension arm can also be damaged. The connector can be damaged and cause a short or open and a code will be set. If one of these sensors is replaced, it must be calibrated after it is installed.

Ride-height sensors are sometimes called suspension-position or wheel-displacement sensors. The data from the sensor is used to measure the movement of the suspension. By knowing how far and fast the suspension is moving, the module can use the information to determine the size of the orifice in the dampener to control compression and rebound.

Measuring Body Movement

Accelerometers are simple devices in theory. Imagine a fishing rod mounted to a moving object like a suspension knuckle. As the object moves, the fishing rod deflects. The faster or further the object moves, the more deflection there is in the fishing rod. An accelerometer is similar to the fishing rod, but instead of a rod, you have an almost microscopic beam mounted between fixed sensing elements. As the beam moves between the fixed elements, the “capacitance” of a circuit changes.

Accelerometers, however, do not measure distance, but rather movement, inertia and gravitational forces. When mounted to the body of the vehicle, the data can be used to see how the movements of the suspension are influencing the body.

Information from the accelerometers is coupled with data from the ride-height sensor, steering sensor and other inputs by a computer processor in a module. The module can determine if the vehicle is going around a corner or traveling down a bumpy road. With this datastream, the valving inside the dampener can be adjusted in milliseconds for the best control and ride quality.

The accelerometers on the body differ from vehicle to vehicle. Some manufacturers mount the sensors under the headlights and near the taillights. Others mount the accelerometers on the strut towers. More sophisticated systems use more than two accelerometers mounted in various locations.

Control Module

The control module for the electronic dampeners needs more than the movement of the wheels and body to determine the correct settings for the dampeners. The module uses and shares information with the anti-lock braking system, engine control module and instrument cluster. This information is typically shared on the high-speed CAN serial data bus. On some BMW 7-Series models, the information is shared on the fiber-optic Flex Ray bus.

With all this information, the module can do some amazing things with the adjustable dampeners. Problems like nosedive under braking, torque steer and understeer on front-wheel-drive vehicles can be minimized. If the vehicle has air ride, the volume and pressure inside the air springs can also be tuned along with the valving in the dampeners to optimize ride quality and control.

Bollinger Motors, a subsidiary of Mullen Automotive, plans to begin production of saleable units of the Bollinger B4 Chassis Cab on September 16, 2024. Deliveries and revenue recognition of the B4 EV truck are expected to begin in October 2024. Bollinger released this video, highlighting the start of production.

Bollinger said its B4 Chassis Cab, a Class 4 commercial truck, was designed from the ground up with extensive fleet and upfitter input. The chassis design encloses and protects the 158-kwh battery pack and components. Bollinger is working on production with Roush Industries, which provides contract manufacturing services from its facility in Livonia, Michigan.

“This is an exciting time in Bollinger Motors’ history, as it takes a monumental team effort to go from start-up to production in the timeframe we have achieved,” said Bryan Chambers, president of Bollinger Motors. “The Bollinger Motors team, Roush Industries and our entire supply chain network has worked tirelessly to make the B4 a reality and I am very proud of everyone’s effort.”

Bollinger Motors recently qualified for federal clean vehicle tax credits under the Inflation Reduction Act of $40,000 per vehicle for the B4 chassis cab.

Look at Ride Height

Suspension angles are dynamic. As the body and suspension moves, the angles will change in the front and rear. OEMs tune these angles for the best tire wear and stability at a set ride height. 

If a spring is weak or missing a coil, the alignment angles will be off these calculations.

Compare Side to Side

Sometimes, a bent component is difficult to spot with the naked eye. If you see a caster, steering angle or SAI reading that is off, compare components on both sides. The key areas to observe are the steering arms, strut mounting points and control arms. Most chassis parts are designed to bend at strategic points to prevent damage to the frame or unibody in the event of a crash.

Don’t forget the tires 

When doing your pre-alignment inspection, always check and set tire inflation pressures. A low tire will cause a pull, and a car also will pull toward the side with the smallest or widest tires. Another factor that could cause a steering pull are variances in the construction of the tires. These types of problems can be diagnosed using a balancer that can measure the rolling forces in the tires. 

Check TSBs

TSBs for alignment issues often have titles referencing tire wear and steering pull complaints. The majority of the TSBs focus on warranty procedures and reimbursement. But, read between the lines and you can find the truth. One Nissan TSB even told technicians to align a vehicle as close as possible to the specifications and ignore the tolerances. Another Honda TSB told technicians to pay attention to plant codes and production dates of a particular tire size and brand to cure a steering pull.

Doubt the Bushings

Suspension bushings may have increased in size, but these bushings can still wear to the point that they will change alignment angles. On the alignment rack, the angles might be within specifications, but loads are put on the bushings during braking, accelerating and corning that could change those angles. The most common sign of a worn bushing is inside edge tire wear and negative toe out.

Going Green Is Not Always Best

Even if all of the angles are in the green, the car may still have an alignment problem. Interpreting the angles and thinking about how an angle on one side can “add up” to trouble on the opposite side is critical for avoiding comebacks. Positive camber on one side with negative camber on the other can add up to a pull, even if the specs are within tolerances, because ±5° on both sides can add up to 10º.

Calibrate and Finish

Many vehicles require that the SAS be reset or recalibrated after an alignment is performed or parts in the steering system are replaced. There are three types of reset procedures: systems that self-calibrate on their own; vehicles that require specific wires or buttons be pressed; and systems that require recalibration with a scan tool. If the SAS is out of calibration, most vehicles can tell if they’re traveling in a straight line. But if the angle is too far off, the ESC could become disabled. Some newer vehicles can automatically calibrate by having the wheel turned from lock to lock and then centered and cycling the key. There are many options for scan tools to reset the SAS. Some tools are even integrated into an alignment system. But, most tools recommend that the calibration be performed on a level surface. Also, it’s a good idea to perform a lock-to-lock turn to complete the calibration.

Success in the automotive aftermarket often stems from humble beginnings and a deep understanding of the industry. Mike Fiorito, the current Director of KYB Americas, exemplifies this journey. His career in the aftermarket began unexpectedly when he took a job as a production and inventory controller at Edelman after graduating from college. Although his background was in marketing, this role provided him with invaluable insights into the industry, starting from the factory floor.

However, Fiorito’s introduction to the automotive world started even earlier, at the age of 15, working at a car wash. The job taught him important life lessons, such as the importance of doing things right the first time and understanding the details of the task at hand—lessons that would stick with him throughout his career.

After gaining extensive experience at Edelman, Fiorito transitioned to Brake Parts Inc., where he spent 17 years, moving through various roles from sales to vice president. This period was instrumental in honing his skills in product management, marketing, and executive leadership, Fiorito said.

When KYB presented an opportunity, Fiorito was initially unsure, but was encouraged by industry peers to take on the challenge. Over time, he assumed the role of Director, leading the company with a focus on product integrity and industry education. Under his leadership, KYB has distinguished itself in a competitive market by offering precisely engineered products tailored to specific vehicles, emphasizing their commitment to quality over quantity.

Fiorito’s career also reflects the value of mentorship, having been guided by several mentors throughout his journey. He now prioritizes mentoring the next generation, ensuring that they gain a comprehensive understanding of the industry, much like he did.

Episode Overview

• Fiorito explains his career path (1:16)
• Fiorito mentions the importance of mentorship (5:25)
• How does KYB differentiate itself in a crowded market? (7:59)
• KYB and sustainability (11:42)
• Lightning Round (15:19)

I read a lot of “case studies” written by technicians online and in magazines. Rarely do I see case studies written by a shop owner who works at the front counter. Here is a story of how high-quality parts can make the customer, technician and me happy.

8:12 am

According to the technician, the test drive revealed something interesting. The ratcheting noise only occurred in 2WD and changed when 4WD was engaged. However, a grinding noise remained no matter what mode was engaged and depended on the vehicle’s speed. Back at the shop, the visual inspection revealed nothing unusual. From previous experience, we knew that the ratcheting noise could be a symptom of an issue with the Ford Integrated Wheel End or IWE.

The system applies vacuum to the actuator when in 2WD. It shuts off the vacuum when in 4WD to engage the hub and axle. This is the reverse of how most locking hubs operate. If there were a vacuum issue, it typically would cause noise from both wheels. But, the noise was coming from only the right front.

The Ford IWE 4WD system does something no other truck can perform. The system not only disengages the hub, but also the axle from the hub. This improved the fuel mileage when the truck is in 2WD. To do this, the IWE actuator moves a collar over a sprocket mounted to the hub unit.

8:30 am

We decided to make sure there was vacuum at the wheel with the engine running. The vacuum gauge revealed there was vacuum being delivered to the IWE actuator. The unit would not hold a vacuum when a vacuum was applied to the actuator using a hand-held pump. We now confirm the IWE actuator at the wheel is malfunctioning. With the vehicle running on a lift, it was easy to tell that the passenger side bearing was making noise compared to the driver’s side. The technician wrote his diagnosis and recommended replacing the actuator and hub unit.

9:15 am

Now, it is time to write the estimate and find the parts. Looking at my suppliers, I can see many options for the wheel hub. Some shops will sort the results by price or delivery time. But I know these are secondary considerations for my customer, who wants the truck to operate with the least possible downtime.

The unit we selected was BCA’s  WE61945 from our local WD. It was not the least expensive nor the one with the fastest delivery, but I know the BCA unit has the highest quality that meets or exceeds the original unit. The IWE actuator was also sourced from the same WD.

9:15 am

Now, it is time to write the estimate and find the parts. Looking at my suppliers, I can see many options for the wheel hub. Some shops will sort the results by price or delivery time. But I know these are secondary considerations for my customer, who wants the truck to operate with the least possible downtime. The unit we selected was BCA’s WE61945 from our local WD. It was not the least expensive nor the one with the fastest delivery, but I know the BCA unit has the highest quality that meets or exceeds the original unit. The IWE actuator was also sourced from the same WD.

9:30 am

We contacted the customer with the estimate for replacing the hub unit and IWE actuator. He texted us back with the two-word response, “Do it.”

12:30 pm

When the parts arrived, we examined the hub unit from BCA. We have ordered other brands of hub units and have had problems. We first noticed that the wheel speed sensor wiring harness was the same length as the original and had the correct connector. We have found that these harnesses can be too long or short on economy units. Many companies will try to go to a length that might fit multiple years or applications.

The other thing we noticed was the sprocket that engages with the axle. The BCA unit uses the same manufacturing processes as the original unit, which secures the cog to the hub unit. The process is called orbital forming, which attaches the cog to the unit. It rolls the lip of the inner race with extreme force to secure the cog to the hub unit. It also sets the pre-load of the tapered roller bearings.

Some manufacturers use alternative processes to secure the cog and set the preload. But, some of these methods do not create a strong bond.

The other issue we have found with IWE units can be the roller bearings inside the axle bore. These allow the axle and hub to move independently. While they don’t support the vehicle’s weight, they keep the axle aligned so 4WD engages effortlessly. Low-quality hub units might develop play that can damage the IWE actuator. Which is what I suspected happened to this truck.

1:04 pm

We started the job once we received the parts, and the technician was free. I knew I had the truck for only a few more hours, so I was dismayed when I saw the technician on his phone in the middle of the job. When I stopped by the bay, the technician wanted to show me something on their phone. This never ends well. I was stunned to see this

All he had to do was scan a QR code included inside the box. I guess this means one less trip to the information station to look up the torque specifications. With the IWE, the torque specifications are critical. This is especially true for the bolt that secures the axle to the flange. This small bolt has a torque specification of only (30 ft/lbs).

2:30 pm

At our shop, the front counter staff must perform a test drive as part of the quality control process. I took the truck for the test drive. The ratcheting and grinding were gone, and the truck shifted into 4WD effortlessly.

4:05 pm

The customer came to pick up the truck and was satisfied. He asked if we could handle a wheel bearing and ball joints on his F-250 next.

This Article is Sponsored By: BCA Bearings by NTN

In this episode of Shop Owner Solutions, Doug Kaufman, editor of Shop Owner Magazine, and Miguel Cornejo, product manager for TrakMotive, discuss the importance and function of driveshafts in vehicles.

“Driveshafts are responsible for transferring torque from the engine to the wheels, allowing the vehicle to move,” explains Cornejo. “They are precision-balanced and weighted to minimize vibration and noise. Of course, the configuration of driveshafts varies depending on the type of vehicle.”

The hosts also highlight the different types of driveshafts and the engineering that goes into their design. They discuss common issues that can occur with driveshafts, such as U joint problems and alignment issues. Diagnostic steps for identifying driveshaft issues are also mentioned, including clunking sounds and vibrations during acceleration.

This episode of Shop Owner Solutions is sponsored by TrakMotive, a leading global manufacturer of new CV axles, ATV and UTV CV axles, driveshafts and window regulators for automotive and light duty truck applications with a continued focus on meeting or exceeding OE specifications on every product.

For more information, visit trakmotive.com.