
When changing a tire, the jack should generally be positioned about 10-20 centimeters away from the tire. Here are some key points to note: 1. Chassis guard plate: Never place the jack directly under the chassis guard plate or the lower control arm of the suspension. Incorrect jack usage or supporting the vehicle at the wrong points can easily cause damage. 2. Hard surface: The correct procedure is to park the vehicle securely, preferably on a level surface, engage the parking brake (for automatic transmission vehicles, shift into P), and ensure the ground where the jack is placed is firm. 3. Hazard prevention: If the ground is soft (such as sand, grass, or mud), it's advisable to place a hard wooden board or stone slab under the jack to prevent sinking or slipping.

I've been running an auto repair shop for over a decade and have seen too many people damage their chassis by jacking at wrong positions. When changing tires, the jack must be placed at the dedicated support points underneath the vehicle - these are located on the metal beam beneath the doors, usually marked by small protrusions or indentations. If you can't locate them visually, get down and feel with your hand; these spots will feel noticeably thicker than surrounding sheet metal. Never jack on plastic fender liners, fuel tanks, or suspension components - these areas can't bear the weight and may either deform or cause dangerous collapses. Always engage the parking brake and shift to Park before lifting. Choose firm, level ground and use wheel chocks on the diagonal tire. If the support point isn't properly aligned, the vehicle will creak and wobble when lifted - immediately lower it and readjust in such cases.

Last time I had a flat tire on the highway, it was my first time changing the spare tire myself and I jacked up the wrong spot. Later, I learned my lesson - there are dedicated jacking points next to each wheel, on the steel beam along the chassis edge, about ten centimeters away from the tire. The easiest way to find them: some cars have triangular symbols on the underbody, while others use raised metal blocks. If you really can't find them, check the owner's manual - it's clearly marked there. Remember to empty the trunk before jacking, otherwise when the car tilts, things might roll out and hit your feet. If the ground is soft, placing a wooden board under the jack makes it more stable. Once I was in a hurry and didn't align it properly - I jacked at an angle and dented the side skirt, costing me over 600 yuan in repairs. That was a painful lesson.

I'm an avid road tripper and have plenty of experience changing tires on the go. The jack placement is actually quite particular—it must be positioned under the square steel beam beneath the car door. You can tell the difference between hollow and solid spots by tapping with your hand. Before lifting, make sure the jack's knob is tightened, and raise it steadily without rushing. A common mistake is jacking up the fuel tank guard or exhaust pipe bracket; these spots can deform and leak oil under pressure. Once the car is lifted, slide the removed tire underneath as a safety measure—it could save your life if the jack fails.

Last week my neighbor's daughter asked me how to use a jack, and I told her the key is to locate the metal reinforcement ribs near all four wheels. Squat down from the front of the car - you'll find the front wheels about 20cm behind the crash beam, and the rear wheels just ahead of the suspension. When jacking, make sure the jack pad fully contacts the support point until it clicks into place. The most common mistake is jacking on plastic underbody panels, which can crack and let rainwater rust the chassis. Once during rainy weather I positioned it wrong - got splashed with muddy water and the car body slid a few centimeters, scaring me into starting over. Safety details really can't be taken lightly.


