torque steer ( alignment) Flashcards
What is torque steer?
Torque steer occurs in front-wheel-drive vehicles when engine torque causes a front wheel to change its angle from straight ahead.
When is torque steer most noticeable?
During rapid acceleration, especially when upshifting of the transmission creates a sudden change in torque being applied to the front wheels.
What effect does torque steer have when turning and accelerating?
Torque steer tends to straighten the vehicle, requiring more effort to make the turn.
What happens if the accelerator is released during torque steer?
A reversing force is applied to the front wheels.
How do manufacturers reduce torque steer?
By keeping drive axle angles low and equal side-to-side.
What design aspects help in equal torque distribution from the engine?
The engine and transaxle being level and the drive axle shafts being kept level.
What should a service technician do regarding torque steer?
Check and correct problems that often cause torque steer.
Is it normal for front-wheel-drive vehicles to exert a tug on the steering wheel during acceleration?
Yes, it is normal for front-wheel-drive vehicles to steer toward one side, usually the right, during acceleration.
How can one determine the severity of torque steer?
By placing a strip of masking tape at the top of the steering wheel and observing the steering movement required to drive straight during heavy acceleration.
What should be done if torque steer is excessive?
Determine and correct the cause by following prealignment inspection steps and checking for a level power train.
What can cause the drive train to sag on one end?
A defective engine mount.
What should be measured to check for level drive axle shafts?
Hold a straightedge along the engine’s supporting frame and measure up to points along the transaxle pan rail or the drive axle shaft.
What is the acceptable side-to-side distance for alignment?
Side-to-side distances should be equal.
What alignment angles should be checked if torque steer is excessive?
SAI and included angle.
What is the acceptable degree variance for SAI and included angle?
Within 1/2 (0.5) degree side-to-side.
Which side will the vehicle pull with SAI?
It tends to pull toward the side with the least SAI.
What can broken or defective engine or transaxle mounts cause?
They can cause the power train to sag, leading to unequal drive axle shaft CV joint angles.
What is the relationship between equal outer CV joint angles and steer torque?
Equal outer CV joint angles produce equal steer torque (toe-in).
What happens if one side receives more engine torque?
That side creates more toe-in, resulting in a pull toward that side during acceleration.
