Chevrolet Sonic Repair Manual: Scrub Radius Description
Ideally, the scrub radius is as small as possible. Normally, the SAI angle and the centerline of the tire and the wheel intersect below the road surface, causing a positive scrub radius. With struts, the SAI angle is much larger than the long arm/short arm type of suspension. This allows the SAI angle to intersect the camber angle above the road surface, forming a negative scrub radius. The smaller the scrub radius, the better the directional stability. Installing aftermarket wheels that have additional offset will dramatically increase the scrub radius. The newly installed wheels may cause the centerline of the tires to move further away from the spindle. This will increase the scrub radius.
A large amount of scrub radius can cause severe shimmy after hitting a bump. Four-wheel drive vehicles with large tires use a steering damper to compensate for an increased scrub radius. Scrub radius is not directly measurable by the conventional methods. Scrub radius is projected geometrically by engineers during the design phase of the suspension.
Replacement Wheels Description
Replace the wheel if any of the following conditions exist:
The wheel exhibits excessive runout.
The wheel is bent.
The wheel is cracked.
The wheel is severely rusted.
The wheel is severe ...
Spare Tire Kit Installation
Installation Instructions Part Number
95280943
Procedure
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Other materials:
Exterior Lighting
The exterior lamp control is on the instrument panel to the outboard side of
the steering column.
O : Briefly turn to this position to turn the automatic light control off or
on again.
AUTO: Turns the headlamps on automatically at normal brightness, together with
the following:
Parking ...
Overview (Radio with CD/USB)
91011121314151617
O /VOL (Power/Volume)
Turns the system on or off and adjusts the volume.
Z (Eject)
Removes a disc from the CD slot.
Buttons 1−6
Radio: Saves and selects favorite stations.
AUX Port
3.5 mm (1/8 in) connection for external devices.
...
Special Tools
Illustration
Tool Number/ Description
CH 28662
J 28662
Brake Pedal Effort Gauge
CH 29532
J 29532
Diaphragm Pressure Bleeder
CH̴ ...
0.0057