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 InstallationTransmission Fluid Pump, Front Differential Carrier Baffle, and Front Differential
Ring Gear Removal (6T40/45)
Transmission Fluid Pump, Front Differential Carrier Baffle, and Front
Differential Ring Gear Removal
Callout
Component Name
1
Front Differential Carrier Baffle Bolts M6 x 25 (Qty: 2)
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Water Outlet Installation
Clean the sealing surfaces.
Install the water outlet (2) and a NEW water outlet seal ring (1).
Caution: Refer to Fastener Caution.
Install the 3 water outlet bolts (3) and tighten to 8 Y (71 lb in).
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Camshaft Sprocket Installation
Install the intake camshaft sprocket (3).
Install the intake camshaft position sensor exciter wheel (2) and the intake
camshaft sprocket bolt (1), but do not tighten yet.
Install the exhaust camshaft sprocket.
Note: Tightening of camshaft sprocket bolts will ...