Chevrolet TrailBlazer, Service Manual, Page: 559 / 677

parking brake adjustment or the wheel alignment. The way in which a tire is built may
produce lead. Rear tires do not cause lead.
Torque Steer
A vehicle pulls or leads in one direction during hard acceleration. A vehicle pulls or leads in
the other direction during deceleration. The following factors may cause torque steer to be
more apparent on a particular vehicle:
A slightly smaller diameter tire on the right front increases a right torque lead.
Inspect the front tires for differences in the brand, the construction or the size. If the
tires appear to be similar, change the front tires from side-to-side and retest the
vehicle. Tire and wheel assemblies have the most significant effect on torque steer
correction.
A large difference in the right and left front tire pressure.
Left-to-right differences in the front view axle angle may cause significant steering
pull in the vehicle. The pull will be to the side with the most downward sloping axle
from the differential to the wheels. Axles (halfshafts) typically slope downward from
the differential. The slope of the transaxle pan to level ground may be used as an
indication of bias axle angles. The side with the higher transaxle pan has the most
downward sloping axle angle.
Memory Steer
Memory steer is when the vehicle wants to lead or pull in the direction the driver previously
turned the vehicle. Additionally, after turning in the opposite direction, the vehicle will want
to lead or pull in that direction.
Wander
Wander is the undesirable drifting or deviation of a vehicle toward either side from a
straight path with hand pressure on the steering wheel. Wander is a symptom of a
vehicle's sensitivity to external disturbances, such as road crown and crosswind. A poor,
on-center steering feel accentuates a wander condition.
Preliminary Alignment Inspection
Perform a number of checks before attempting a vehicle alignment. Loose or worn
suspension parts prevent an accurate setting of alignment angles. Checks should include:
The tires should be checked for proper inflation pressures.
Check the tires for normal tread wear.
Check the front hub and bearing assembly for excessive wear.
Check the ball joints and tie rods for looseness.
Inspect the wheels and tires for runout, resulting from bent wheels or faulty tires.
The vehicle trim height should be checked. If the trim heights are not within
specification, it will be necessary to make corrections before adjusting the
alignment.
The steering gear should be checked for looseness.