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Torque steer is a condition in which the vehicle pulls to one side or the other under acceleration.
Technically, torque steer is a result of a mechanical condition,
typically an inequality between the left and right drive mechanism,
wheels or tires. Automotive engineers have all but eradicated inherent
torque steer in new front-drive vehicles by employing equal-length drive
axles, or “half-shafts,” on each side, and other measures. Right or
wrong, nowadays the term torque steer is used to describe virtually any
disturbance — such as straying from straight-line progress or tugging in
the steering wheel — resulting from the front pair of wheels being
asked both to power and steer the vehicle. Typically this is caused by a
loss of traction by either front wheel, whether it’s due to slippery
conditions or an overenthusiastic accelerator foot.
True, mechanically induced torque steer may have been minimized, but
the simple loss of traction in powered front wheels seems inevitable. If
the car has any torque to speak of, it will cause the tires to lose
their grip under heavy acceleration or turns, especially in low-traction
situations. This is precisely why few front-wheel-drive vehicles are
considered true sports cars. Front-wheel drive is often lauded for its
improved traction, but that is more about clawing through snow or wet
roads at low speed. Here, having the engine’s weight over the drive
wheels is advantageous. When a vehicle accelerates hard, however, much
of its weight shifts to the back over the rear wheels. This benefits
rear-wheel-drive cars and disadvantages those with front-wheel drive.
It’s a paradox: The more power an engine has to lurch forward, the more
it’s lifting weight off the front wheels.
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