Suspension System Questions

Suspension System

Are struts simply oversized shocks

strut diagram

strut cartridge

A strut performs the same ride control functions as a shock absorber, but it is also an integral part of the suspension rather than an add-on component.

strut assembly

On most strut suspensions (except some late model Honda applications that have “wishbone” suspensions), the struts replace the upper control arms and ball joints.

rear strut

The 1986 Honda Accord has a rear double-wishbone suspension. The strut plays no role in wheel alignment in this arrangement, serving only to carry the vehicle’s weight and to dampen shocks.

Struts serve as the steering pivots and on most applications (except certain Ford suspensions like the Mustang and T-Bird), they also carry the springs. On some rear-wheel drive strut suspensions, the wheel spindles are part of the front struts (which adds to their cost). The same is true on some front-wheel drive rear strut applications.

Another important difference between struts and shocks is that struts also affect wheel alignment, whereas shocks do not. A bent strut or a mislocated strut tower can cause tire wear and steering pull problems.

Many struts are also rebuildable. On many import cars, the struts have an internal cartridge or wet elements that can be replaced by unbolting the upper strut mount, swinging the strut out from under the fender, disassembling the upper strut components, and replacing the internal components with a new cartridge.

On most domestic applications, however, the entire strut must be replaced. Replacement options include both nonpressurized and gas pressurized versions, the latter offering all the same benefits as gas shocks.

One often overlooked strut component that usually needs attention is the upper bearing plate that sits atop the strut. This plate supports the weight of the vehicle and serves as the upper pivot point for steering. If corroded or worn, it can make noise, increase steering stiffness and reduce steering returnability.

 

Computerized Wheel Alignment

We Measure and adjust the alignment angles of each wheel to meet manufacturers specifications.

Types of Alignment (old and new)

Front End Alignment (old)

  • Front wheels are aligned relative to geometric center-line
  • Steering wheel may not be centered

Align 1

 

Computer Wheel Alignment (new)

  • Front wheels are aligned while referencing and compensating for thrust line
  • Steering wheel is centered
  • For vehicles with non-adjustable rear suspensions

Align 2

 

Computer Four-Wheeled Alignment (new)

  • All four wheels are aligned while referencing and adjusting thrust line
  • Maximum mileage from all four tires
  • Steering wheel is centered
  • Vehicles with adjustable rear suspension

Align 3

 

Do wheels have to be realigned when struts are replaced?

Most of the time, but not always. It depends on the application. When a McPherson strut is replaced on a vehicle where the strut is an integral part of the suspension and it has provisions for camber and/or caster adjustments, the original wheel alignment settings are lost when the strut is removed.

Even if the position of camber bolts and/or upper camber/caster plate is carefully marked prior to removal, variations in manufacturing tolerances between the original strut and its replacement will probably alter suspension geometry enough to require realigning the wheels.

On vehicles with “wishbone” strut suspensions, the strut doesn’t play a role in wheel alignment. On these vehicles, realignment of the wheels after replacing the strut is not necessary.

On vehicles with rebuildable struts, it is not necessary to realign the wheels if only the strut cartridge is being changed. It is necessary to mark the original positions of the upper strut plate and/or lower camber prior to unbolting anything to preserve the original alignment settings.

 

 

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All Around Automotive Repair Inc. is a full-service automotive repair and detail shop—but with a unique calling: to provide affordable service to the entire community regardless of financial circumstances.

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