Tip - How to Shift a Chevrolet S-10 4WD Auto Transmission Into 4L | eHow

4L is recommended only in extreme conditions, such as deep snow, off-road mud or sand, or steep declines, according to the S-10's owner's manual. This setting sends maximum power to your front and rear axles, allowing you to gain extra traction. 4L should not be used for normal driving. However, there may come a time when you need to engage the...