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
Spare Tire Kit InstallationRoadside Assistance Program
For U.S.-purchased vehicles, call 1-800-243-8872; (Text Telephone (TTY): 1-888-889-2438).
For Canadian-purchased vehicles, call 1-800-268-6800.
Service is available 24 hours a day, 365 days a year.
Calling for Assistance
When calling Roadside Assistance, have the following information ready:
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Wireless Communication Interface Antenna Replacement
Wireless Communication Interface Antenna Replacement
Callout
Component Name
Preliminary Procedure
Remove the communication interface module. Refer to
Communication Interface Module Replacement
1
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Engine Replacement (Automatic Transmission)
Special Tools
J-45859 Wheel Drive Shaft Remover
CH-807 Closure Plugs
For equivalent regional tools, refer to Special Tools.
Removal Procedure
Remove the battery and battery tray. Refer to
Battery Tray Replacement.
Relieve the fuel system pressure. Refer to
Fuel Pre ...