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How to Use a Jack and Jack Stands

 

Average Repair Cost & Time
Avg. Repair Time
5-15 minutes

Difficulty Level

Beginner
Expert

Overview

Many automotive repairs require that you lift your car or truck off the ground in order to gain access to underbody components. With a jack and jack stands you can lift one corner of the car, one end of the car, or the entire car. And you can do it safely.

Lifting a vehicle of several thousand pounds off the ground is potentially dangerous. Failure to follow safe lifting practices can lead to serious injury or fatality. Professionals take the time to practice safe shop habits every time a vehicle needs to be lifted. It is also possible to damage underbody components if they are not strong enough to bear the weight of the vehicle. The suggestions in this article are a guide to help you develop safe habits and to help you to avoid accident, injury, or damage to your vehicle. But there is no article that can substitute for common sense.

Select the Right Equipment for Safety

Of course, your car comes with a jack to use if you have to change a flat tire on the side of the road – usually a bottle jack or a scissor-jack that is lightweight, simple to operate, and shares a small space with a tool kit in your car. But while this portable picker upper might be good in a pinch, it does not offer the stability and strength necessary for a safe repair. A floor jack and jack stands are the better – and safer – option.

The Floor Jack

(Courtesy of thesmartconsumer.com)

A hydraulic floor jack (also known as a "service jack" or "car jack") delivers more stability than other portable jacks. Options range from small, lightweight consumer models that come with a carrying case, to larger, heavier, and higher-capacity models used by professionals. An inexpensive floor jack with a 2-ton lifting capacity can be purchased for less than a hundred bucks; a 3-ton heavy duty professional jack might run closer to $400. Generally speaking, the higher the quality, capacity, and durability, the higher the price – and the greater the peace of mind it provides.

There are also specialty jacks that are designed for specific applications: low profile jacks for cars with low ground clearance; high-lift jacks for trucks or large SUVs; long-reach jacks for large vehicles; and rapid pump models for speed.

The Jack Stands

(Courtesy of heinwerner-automotive.com)

The purpose of a floor jack is to raise and lower a vehicle, NOT to support a vehicle during repairs. Once a car or truck has been lifted with a jack, it must be supported on a quality (and properly rated) set of jack stands placed at each corner of the car that is off the ground. If you are lifting a small car, a set of well-made 2-4 ton jack stands should be sufficient. On the other hand, if you are lifting a larger car or a truck, or if you are lifting any vehicle high off the ground, a more substantial set should be used. In any case, jack stands are not optional. They are essential.

A professional technician knows to never crawl under a lifted vehicle unless it is resting firmly on a pair of jack stands!

Full-Frame vs. Unibody Construction

(Courtesy of trucktrend.com)

How you lift and support your vehicle may depend on whether it has a full-frame or a unibody design. Most trucks, many SUVs, and some big-bodied cars have a full (or conventional) frame that is separate from the vehicle body. This frame extends from the front to the rear of the vehicle and supports all of the drivetrain and suspension.

(Courtesy of howstuffworks.com)

A unibody is a vehicle that is built as a single unit of welded and bonded sheet metal where the body and the “frame” are integrated. Most passenger cars and light SUVs are unibody construction and do not have a full frame. Instead, they have small fortified frame members (called crossmembers) bolted to the body that support the engine and suspension. Lifting a full-frame vehicle is usually pretty straightforward; lifting a unibody car can take a bit more skill.

Locating Lift Points

The vehicle manufacturer provides set locations, or lift points, for your vehicle. Check your owner’s manual or a repair manual (click here for a link to Chilton’s Online Manual), for the factory lift point locations on your specific vehicle.

On a full-frame vehicle the recommended lift points are usually under the frame.

On a unibody they are usually found at the ends of the rocker panels (just behind the front wheels and ahead of the rear wheels) and can be identified by a notch or projection in the flange on the bottom of the panel.

In addition to locating the factory lift points, you will also have to locate alternate lift points. The factory lift points are often best suited for placement of the jack stands. Since you can’t place a jack stand in the same spot occupied by the jack, you will need another place to put the jack (as in the photo above).

Look for locations that are free from brake lines, fuel lines, or electrical wires.

A full-frame presents several sturdy options along each frame rail, as well as under crossmembers that connect each side. Even the differential (if it is not made of soft aluminum) can be used to lift a rear-wheel-drive vehicle, and the axle can be used for support. Position the jack stands as far apart as possible to provide a stable stance, and make sure they are under a level section of frame (not on an angle).

Unibody construction calls for a bit more critical thinking. It is essential that you identify strong surfaces that will not deform, and stable components that will not shift, when placing a jack or jack stand (the photo above shows a reinforced section of a unibody frame member).

Consider suspension crossmembers (above photo), welded frame members, reinforced suspension mounts, or even tow hooks attached to frame members, as opposed to sheet metal underbody panels (footwell, trunk floor).

Some front-wheel-drive unibody cars have a trailing axle that may be safe for lifting; some axles will not support the weight. Some have reinforced mounts near the trunk floor designed to be used as a lift point. Many do not. DO NOT lift using engine or drivetrain components – such as the oil pan or transmission – or moveable suspension parts or torsion rods.

Before You Begin

Before you begin any repairs, it is wise to follow a few basic safety precautions. Use personal protective equipment such as a pair of gloves to protect your hands. Shield your eyes with safety glasses or goggles. Be aware of anyone who might be in the area of your repairs. And make sure to use the proper tools and equipment to prevent injury to yourself or damage to your car.

Once you have ensured your safety, and the vehicle is in position for repairs, you are ready to begin.

What You Will Need:
  • Floor jack
  • Jack stands
  • Steel plates or playwood panels (for jack stands placed on asphalt)

Place the vehicle on a solid, flat surface. Put the vehicle in park and set the parking brake. Place a wheel chock or wood block behind a rear tire to further prevent the vehicle from rolling while you lift it off the ground. Locate both the recommended lift points and alternate lift points.

If you need to remove a wheel, use a breaker bar and socket to loosen – but not remove – all of the lug nuts before you lift the vehicle off the ground.

If you have access to a pneumatic impact wrench you can skip this step and remove the wheel when the vehicle is off the ground.

Raise the Front of the Vehicle

Some vehicles have a suitable lift point (front crossmember, tow hook, or suspension mount) that will allow the entire front end to be lifted at once. This allows you to place a pair of jack stands under the factory lift points for support. Other vehicles require that you lift only one corner at a time.

Make sure that there are no brake lines, fuel lines, or electrical wires that might get pinched by the jack or jack stands.

If you are lifting the whole front end at once, make sure that the vehicle rises evenly to the desired height. Otherwise, raise one side at a time.

Make sure the valve on the jack is gently closed or snug (do not overtighten) by either turning the jack handle clockwise, or, on some models, by closing a release screw on the rear of the jack body. Pump the jack handle up and down to actuate the jack and lift the vehicle.

Place the Jack Stands

Place jack stands under the recommended lift points (or under alternate lift points) and slowly lower the vehicle onto the stands Consider leaving the jack in place and in contact with the vehicle as an added safety measure.

it is important that you always place the jack stand under the vehicle using only your arm to prevent serious injury in the event that the hydraulic jack fails!

Raise the Rear

When you pick up the back end of a vehicle it is important to block the front wheels to prevent the vehicle from rolling. Once you have identified a safe and solid lift point (differential, tow hook, rear trailing axle), place your jack and lift the entire back end at once. Make sure that both sides of the vehicle rise evenly.

Place jack stands under the factory lift points or under suitable locations on the frame (preferably the same location on each side) or rear axle. Make sure the jack stands are set to the same height to keep the vehicle level and balanced. Remember, it may be necessary to raise one side at a time.

If you are lifting the entire car – front and rear – try to discern whether you will have enough clearance for the jack underneath the vehicle once the first end is in on jack stands. Sometimes the front bumper is too low to the ground for the jack to travel underneath once the back end is on stands. Also, if you have to lift one corner at a time, lift that end first. It is better to raise the right front corner of the car with the rear tires on the ground for stability than with the rear end already on jack stands.

Lower the Vehicle

To lower the vehicle, use the jack to raise either the front or rear slightly, remove the jack stands (with only your arm under the vehicle), check to make sure the area under the car is clear, and slowly lower the vehicle.

To lower the car slowly and gently, remember to close the hydraulic pump valve on the jack gently. Do not overtighten. Otherwise, when you strain to release the pressure in the jack, the vehicle will lower abruptly and could cause injury.

If you removed and reinstalled the wheels, torque the lug nuts to the manufacturer’s recommendation once the vehicle is on the ground.

Lifting a vehicle can be done safely if you practice safe shop habits every time you use a jack and jack stands to lift and support a vehicle. Refer to the RepairPal How-to Guides & Videos page for more car care advice articles.

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