AfterMarketNews 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

Using Your Oscilloscope: Current Ramp Test Ignition Coils

Regardless of design configuration, the role of the ignition coil is to multiply battery voltage into high voltage. Following Ohm’s law for the conversion of volts to amperes, oil-filled coils generally require 3 to 5 amperes of primary current...

Read more...

Serial Data Bus Diagnostics

Understanding The Function of Serial Data Buses If serial data buses did not exist, a wiring harness would have to be five times its normal size and use twice as many sensors to deliver the same level of functionality and safety we see in the modern...

Read more...

Throttle-By-Wire Codes: P1512 On 2002 GMC Envoy

The PCM continuously monitors the commanded and actual throttle positions. The commanded throttle position is compared to the actual throttle position based on ­accelerator pedal position and possibly other limiting factors, and both values should...

Read more...

GM Power Steering Noise/Leaks

GM: Power Steering Noise/Leaks from Power Steering Pump, Gear or High Pressure Hose During Extreme Low Temperature Conditions MODELS: -2009-2015 Buick LaCrosse (Equipped with Hydraulic Power Steering) -2010-2013 Buick Regal -2012-2015 Buick...

Read more...

Ford Edge Brake Replacement

Ford Edge Brake Replacement Basics The Ford Edge is an SUV based on the CD3 platform. The brakes on these vehicles are straightforward and do not break any new ground. There were no major changes to the brake systems from 2007 to the current model. For...

Read more...

Live-Axle Wheel Bearing Replacement

Replacing wheel bearings on a vehicle with a live rear axle may not be one of the most frequent jobs, but it can be one of the most profitable. While the basics have not changed in more than 60 years, new seal materials and differential designs have...

Read more...

The Ins And Outs Of Sanders

Sanders are required tools in today’s collision repair shop. Body techs and painters rely upon them every day to achieve that perfect finish on your customers’ vehicles. Whether you’re prepping a panel for paint or removing imperfections before...

Read more...

Are You Regularly Maintaining Your Equipment?

Technicians who are idling because the welder won’t feed wire, the hydraulic ram won’t pull chains, the booth heater won’t heat or the air compressor won’t compress enough air is a costly mistake, as labor time is the most expensive thing in any...

Read more...

Celebrate 'Back To The Future' Day By Watching The Time Machine Get A 2015 Detail

    For many today is just another Wednesday, but for a lot of people it is more than just your average Wednesday, it is "Back to the Future" Day. It is a day that everyone who watched the cult classic trilogy Back to the Future recognizes...

Read more...


Home European When To Replace Steering Knuckles and Arms

Print Print Email Email

ight passenger side because the right wheel is more apt to hit a curb than the left wheel.

CAMBER CLUES
Tire wear can also be affected by camber. Excessive camber loads one side of the tread more heavily than the other, resulting in uneven wear. Camber wear typically produces uneven wear on one side of the tire tread. If the inside of the tread is worn off, the wheel has too much negative camber. A worn outer tread indicates too much positive camber.

Camber can also affect directional stability. A vehicle will lead toward the side with the most camber. So always compare camber readings on both sides. More than half a degree difference can cause a steering pull.

If camber is off on one side only, a close encounter with a pothole or curb may have bent a spindle, control arm or strut. A shift in the position of a strut tower can cause the same thing. A shift in the position of a crossmember, on the other hand, will usually change camber on both sides. In MacPherson strut suspensions, the position of the upper strut tower is critical. Too far in and the wheel will have too much negative camber. Too far out and it will have too much positive camber. A bent strut or spindle can affect camber as can a bent control arm, a mislocated crossmember or an off-center engine cradle in a FWD car.

One way to identify hidden damage that may be affecting camber is to do a “jounce/rebound camber check.” Raise the suspension four inches and read camber on both sides. Then compress the suspension four inches and read the camber angles for both wheels again.

Different side-to-side camber readings with a jounce/rebound camber check usually indicates a bent strut that needs to be replaced or straightened. If the readings are the same, a check of the “steering axis inclination” (SAI) angle side-to-side should also be made.

SAI, THE DIAGNOSTIC ANGLE
SAI is a “built-in” angle that can help you detect all kinds of hidden damage. SAI is the angle of the steering axis and runs from the center of the upper ball joints or strut towers through the center of the lower ball joints. SAI should always be the same on both sides. A difference of more than a degree usually indicates a mispositioned strut tower, bent spindle or control arm.

It’s important to always check SAI even if no specs are provided because unequal SAI side-to-side (even if camber is within specs) can contribute to torque steer, brake pull during sudden stops and even bump steer. You can zero in on the hidden damage (a bent or mislocated strut, bent control arm and/or bent spindle) by comparing the SAI angle, camber reading and “included angle” (the angle between camber and SAI). See the above SAI diagnosis chart.

Here’s another way to check for strut problems. Loosen the two camber adjustment cam bolts on the strut (if provided), push the steering knuckles in as far as they’ll go toward negative camber and measure the distance between the strut and brake rotor on both sides. Then compare readings. If both distances are the same, you can rule out misalignment at the bottom end of the strut or a bent spindle. If they’re different, one of the struts is bent.

Bending a strut to “realign” the front end is no answer because you shouldn’t fix one problem by creating another. Bending a strut may bring camber back into range ‹ assuming the wheel isn’t off more than one and a half degrees (which is the maximum limit for bending any strut). But bending a perfectly good strut to compensate for misalignment elsewhere is going to create unequal camber changes side-to-side during jounce and rebound, which may create a bump-steer condition. There is also a risk of weakening the strut, which may lead to strut failure later.

To check for a bent strut shaft, loosen the large shaft nut at the top of each strut and rotate the shaft 360° while keeping an eye on the camber reading. If the shaft is bent, the top of the wheel will wobble in and out, and the camber reading will change as the shaft turns. No change in the camber reading means there’s nothing wrong with the strut. A strut with a bent shaft must be replaced. There’s no way to safely straighten this kind of damage because attempting to bend a hardened shaft will likely crack it.

The following two tabs change content below.
Larry Carley

Larry Carley

Larry Carley has more than 30 years of experience in the automotive aftermarket, including experience as an ASE-certified technician, and has won numerous awards for his articles. He has written 12 automotive-related books and developed automotive training software, available at www.carleysoftware.com.
Latest articles from our other sites:

Cool Under Pressure: Choosing The Correct Coolant For The Job

Modern coolants, in their many colors and compositions, have helped extend the service intervals and replacement schedules of cooling system components. Driven in part by the OEMs longer powertrain warranty,...More

Dayco Unveils New Tagline And Identity Statement

Dayco recently unveiled “Move Forward. Always.” as its new tagline. The company says this simple, yet strong, statement is an important part of its new global brand strategy, and reflects the company’s...More

Focus On Brake Friction For Safety

A vehicle’s ability to stop quickly, safely and quietly depends on the condition of its brake pads. The pads create friction when the brakes are applied, converting the kinetic energy of motion into...More

Raybestos Adds Police Brakes To Brake Products Lineup

Raybestos has expanded its family of brake products with the addition of disc brake pads and rotors specially manufactured to meet the demands of law enforcement professionals. The new Raybestos Police...More

Urethane Supply’s Plastic Welder Features Self-Contained Nitrogen Generation System

Urethane Supply Company offers its new 6066-CG Nitrocell Nitrogen Plastic Welder. Nitrogen welding is a fast and efficient way of repairing damaged thermoplastic vehicle body panels, and the new 6066-CG...More

Compact Impact Wrench from Beta Tools Packs Power

Beta Tools offers the 1927 XM/K5, which includes a one compact reversible impact wrench and five impact sockets all in a plastic case. Compact and powerful, this 770 Nm single hammer impulse device...More