How to Use a car jack to replace a tire
Everyone who drives should know how to use a car jack in case of a flat tire or blowout. Check your owner's manual to find out where your car jack and spare tire are located. In most cases, they are somewhere in the rear of the car.
how to use a telescoping jack, though the more common type of jack requires a scissor motion to raise the car and lifts from the side rail. The telescoping jack lifts from the axel and to raise the jack you need to insert the rod into the hole near the base of the jack and turn clockwise. Make sure that the groove in the jack fits securely into the place where it comes into contact with the axel to avoid any slippage as the car lifts off the ground. You also may want to place blocks against the tires so the car won't roll. Make sure that the car is on a level surface before you use the jack. Finally, if you are not comfortable using the jack then call a professional service to do it for you.
Auto Repair: How to Use a Jack Safely
The most obvious reason to jack up a car is to change a tire, but other jobs such as inspecting brakes may also require you to get under the vehicle. (Even if you're skinny enough to squeeze yourself between the pavement and the underside of your car, you still need room to move around and manipulate tools.) This section explains how to use a jack safely and efficiently.
Caution: Before you attempt to jack up your vehicle, observe the following safety precautions:
Tip: If you find yourself faced with the job of changing a tire and you have nothing with which to block the wheels, park near the curb with the wheels turned in. This may not keep you from getting hurt if the car rolls off the jack, but at least innocent motorists and pedestrians won't have to deal with a runaway driverless vehicle!
Never change a tire on a freeway or highway.
Not only can you be seriously injured, but you can also fall prey to carjackers. Don't exit the vehicle; instead use a cellphone to call road service or an automobile association such as the AAA. If you don't have a cellphone, hang a white rag or a white piece of paper out of the driver's side window and wait for the highway patrol to rescue you.
CarSmarts: Even if you hate cellphones, I recommend that you buy one and keep it in the vehicle for emergencies. You can find a very affordable model that just lets you call 911, road service, and those you'd want to notify in an emergency. It could save your life.
Always park a vehicle on level ground before you jack it up. If you get a flat tire on a hill and can't coast to the bottom without killing the tire completely, park close to the curb, turn the wheels toward the curb, and block the downside wheels securely to prevent the car from rolling.
Remember: These precautions won't eliminate the risk of changing a tire on an incline. If you can't get to level ground or wait for assistance, you change the tire at your own risk.
Be sure that your gearshift is in Park (or in First if you have a manual transmission) and that the parking brake is on before you jack up the vehicle. The only time you don't want the parking brake on is when you have to be able to rotate a rear wheel or remove rear brake drums to inspect the brakes. In such a case, make sure that the front wheels are blocked securely.
Caution: If you remove a wheel and begin to work without making sure that you jacked up the car and blocked it securely, the vehicle can do a lot of damage to itself -- and to you -- if it falls. (This is not meant to frighten you away from jacking up your car and working on or under it. It's just to emphasize the fact that taking a few simple precautions can keep you safe.)
After you've observed all the safety precautions, follow these steps to jack up a vehicle:
1. If you're going to remove a wheel to change a tire or check your brakes, remove the wheel cover or hubcap (if there is one) and loosen the lug nuts.
After the vehicle is jacked up, the wheel will turn freely, which makes it harder to get a wheel cover off and almost impossible to start turning the nuts. Instructions for removing a wheel cover and loosening lug nuts are in the next section, "How to Change a Tire."
2. Place the jack under the part of the vehicle that it should contact when raised. If you're using jack stands, place them near the jack.
Where you place your jack depends on whether you're planning to do a one-wheel job, such as tire changing or brake checking, or a two-wheel, whole-end repair job. Many vehicles now have special flat spots on the underside specifically for jack placement.
Tip: If you place your jack incorrectly, you can injure your car. To find the proper place to position the jack for your particular vehicle, check your owner's manual. If you don't have a manual, ask the service department at your dealership to show you the proper placement. In any event, follow these guidelines:
4. Place the jack stands under the vehicle, near where the jack is touching it (see Figure 1-2). Raise the stands until they're high enough to just fit under, and lock them in place. Lower the jack until the vehicle is resting on the jack stands.
Caution: Substituting boxes, stones, or bricks for jack stands is very dangerous. They can slip out or break while you're under the car. A jack can do the same thing, so be sure to buy a pair of jack stands and stow them in the trunk if you're traveling out of reach of help if you get a flat tire.
5. Before you begin to work, wiggle the vehicle a little to make sure that it's resting securely on the jack stands. Then remove the jack.
Wiggling the vehicle also tells you whether you have the wheels blocked properly. It's better if the vehicle falls while all four wheels are in place. (It will bounce just a little.)
6. When you're finished working, replace the jack, remove the stands, and lower the vehicle to the ground.
If you're using a scissor jack, simply turn the crank in the opposite direction. If you're using a hydraulic jack, use the rod to turn the pressure release valve. The jack will do the rest of the work for you.
Caution: Before you attempt to jack up your vehicle, observe the following safety precautions:
- Jacks are used only to get a vehicle off the ground. They should never be used to hold a vehicle in place.
- You must use jack stands when you work underneath your vehicle. If you don't, you run the risk of serious injury or even death. People have been crushed to death when vehicles that were improperly secured fell on them.
- Never jack up a vehicle without blocking the wheels to keep it from rolling. Use bricks, wooden wedges, or metal wheel chocks to block the wheels at the opposite end of the car from the end that is to be raised. (Chocks are available at a low cost at auto supply stores.) Keep whatever you use for blocks in the trunk so that you don't have to go hunting around if you have to change a flat tire.
Tip: If you find yourself faced with the job of changing a tire and you have nothing with which to block the wheels, park near the curb with the wheels turned in. This may not keep you from getting hurt if the car rolls off the jack, but at least innocent motorists and pedestrians won't have to deal with a runaway driverless vehicle!
Never change a tire on a freeway or highway.
Not only can you be seriously injured, but you can also fall prey to carjackers. Don't exit the vehicle; instead use a cellphone to call road service or an automobile association such as the AAA. If you don't have a cellphone, hang a white rag or a white piece of paper out of the driver's side window and wait for the highway patrol to rescue you.
CarSmarts: Even if you hate cellphones, I recommend that you buy one and keep it in the vehicle for emergencies. You can find a very affordable model that just lets you call 911, road service, and those you'd want to notify in an emergency. It could save your life.
Always park a vehicle on level ground before you jack it up. If you get a flat tire on a hill and can't coast to the bottom without killing the tire completely, park close to the curb, turn the wheels toward the curb, and block the downside wheels securely to prevent the car from rolling.
Remember: These precautions won't eliminate the risk of changing a tire on an incline. If you can't get to level ground or wait for assistance, you change the tire at your own risk.
Be sure that your gearshift is in Park (or in First if you have a manual transmission) and that the parking brake is on before you jack up the vehicle. The only time you don't want the parking brake on is when you have to be able to rotate a rear wheel or remove rear brake drums to inspect the brakes. In such a case, make sure that the front wheels are blocked securely.
Caution: If you remove a wheel and begin to work without making sure that you jacked up the car and blocked it securely, the vehicle can do a lot of damage to itself -- and to you -- if it falls. (This is not meant to frighten you away from jacking up your car and working on or under it. It's just to emphasize the fact that taking a few simple precautions can keep you safe.)
After you've observed all the safety precautions, follow these steps to jack up a vehicle:
1. If you're going to remove a wheel to change a tire or check your brakes, remove the wheel cover or hubcap (if there is one) and loosen the lug nuts.
After the vehicle is jacked up, the wheel will turn freely, which makes it harder to get a wheel cover off and almost impossible to start turning the nuts. Instructions for removing a wheel cover and loosening lug nuts are in the next section, "How to Change a Tire."
2. Place the jack under the part of the vehicle that it should contact when raised. If you're using jack stands, place them near the jack.
Where you place your jack depends on whether you're planning to do a one-wheel job, such as tire changing or brake checking, or a two-wheel, whole-end repair job. Many vehicles now have special flat spots on the underside specifically for jack placement.
Tip: If you place your jack incorrectly, you can injure your car. To find the proper place to position the jack for your particular vehicle, check your owner's manual. If you don't have a manual, ask the service department at your dealership to show you the proper placement. In any event, follow these guidelines:
- Never place the jack so that the weight of the vehicle rests on something that can bend, break, or give.
- If your manual is incomprehensible or lacks jack placement information, try to place the jack so that it touches either the vehicle's frame or the big bar that supports the front wheel suspension.
- You can also place jacks near the rear-wheel axle, but until you become more proficient at this, I'd stick to jacking up one wheel at a time.
- If you have a scissor jack, insert the rod or wrench over the knob, and then crank.
- If you have a hydraulic jack, place the handle into the appropriate location and pump up and down. Use nice, even strokes, taking the jack handle from its lowest point to its highest point on each stroke to cut down on the labor involved.
4. Place the jack stands under the vehicle, near where the jack is touching it (see Figure 1-2). Raise the stands until they're high enough to just fit under, and lock them in place. Lower the jack until the vehicle is resting on the jack stands.
Caution: Substituting boxes, stones, or bricks for jack stands is very dangerous. They can slip out or break while you're under the car. A jack can do the same thing, so be sure to buy a pair of jack stands and stow them in the trunk if you're traveling out of reach of help if you get a flat tire.
5. Before you begin to work, wiggle the vehicle a little to make sure that it's resting securely on the jack stands. Then remove the jack.
Wiggling the vehicle also tells you whether you have the wheels blocked properly. It's better if the vehicle falls while all four wheels are in place. (It will bounce just a little.)
6. When you're finished working, replace the jack, remove the stands, and lower the vehicle to the ground.
If you're using a scissor jack, simply turn the crank in the opposite direction. If you're using a hydraulic jack, use the rod to turn the pressure release valve. The jack will do the rest of the work for you.
How to Use Hydraulic Car Jacks
Unlike traditional screw jacks that are manipulated with long cranks, hydraulic car jacks use high-pressure liquid displacement to lift cars. If employed properly, hydraulic car jacks are easy to use for most people and provide more power than ordinary, mechanical screw jacks.
Instructions
Locate the jacking point, which is usually found about one foot behind or in front of the wheel on which you are working. Check your owner's manual if you have trouble locating it.
Stack the plywood and place the stack on the ground where you plan to use the hydraulic jack.
Set the jack on a stable point on the plywood stack.
Loosen the wheel you plan to work on before you jack up the car. Otherwise, the force you will exert to loosen the wheel may cause the jack to tip over.
Release the locking mechanism located on the hydraulic jack handle. This mechanism allows you to lock the handle safely when it's not in use.
Jack up the car by operating the lever on the hydraulic jack. Move the lever or jack handle up and down to raise the car about 1 1/2 inches off the ground.
Place the jack stand under the axle-stand point underneath the car but never under the axle itself. Check the owner's manual if you are not sure where the axle-stand points are located.
Remove the jack stand when you are finished working on the car.
Lower the car until the jack is no longer supporting its weight.
How to Lower a Hydraulic Car Jack
Cars Auto Repair Do It Yourself Auto Repair
Anyone that plans on handling some of their own car maintenance or repair will eventually need to use a hydraulic car jack. The fact that these tools will be lifting and holding thousands of pounds means it is important that anyone using a hydraulic car jack know how to properly operate it. Lowering the jack in a safe manner is an important part of using a jack.
Instructions
Practice raising and lowering the jack without a load first before using the jack in a situation where it is supporting the car. Determine whether the jack is lowered by simply twisting the jack handle in a counterclockwise direction. If not, it will be lowered by removing the handle, placing the end of the handle over a notched screw located just below where the jack handle attaches to the jack, and then twisting the jack handle in a counterclockwise direction.
Inspect the jack stand to make sure they are located properly, or inspect the ground area to make sure there are no obstacles before lowering a vehicle.
Say "Clear" loudly as a safety double check in alerting others that you are now going to lower the vehicle.
Lower the vehicle down onto jack stand or back to the ground easy, by slowly turning the jack handle and controlling the rate of descent of the car.
procedure for replacing a flat tire
lower the car down on to our spare tire and we are going to follow the same procedures as we did for raising it. We are going to go ahead and lower our emergency jack here and as we continue to get it a little bit lower, the tire is going to start to touch the ground. Now as it starts to touch the ground, you are going to want to make sure to watch and make sure that the tire doesn’t tip out and that it is sitting squarely. Go ahead and continue lowering your jack until your tire just hits the ground where it won’t roll anymore in the air.
A car jack is the primary tool for changing flat tires. Learn how to safely lift your automobile using an emergency jack
emergency jack which is also known as a spare tire jack. When you get your emergency jack from your trunk, what you will want to do is position it underneath your lift points on your vehicle and start cranking it up. Now with emergency jacks, nobody likes them, they are not very fun and they take forever but in case of an emergency, they work great. Once the jack meets that lift point, you want to continue to slowly raise it, and test to make sure that the jack is secure and continue to raise it some. Test it again and typically I will not have my hand underneath it while I raise it in case the jack slips out or the car falls, so you can continue to raise it up until you have your desired height.
Finding and buying the best car jack
A car jack buying guide
Whether you need to change a tire at the side of the road or want to conduct your own major auto repairs in your garage, a top rated car jack deserves a key place among your automotive tools and equipment. Despite the many types of car jacks from which you can choose, it's easy to decide which car jack to buy. Just consider your vehicle's dimensions and how often you expect to use your new jack.
What kind of vehicle do you drive?
types of car jacks
Most auto and tires sections carry a wide assortment of one-car jacks. To find the best car jacks for you and your vehicle, start by understanding your vehicle weight and clearance height. The car jack model that suits you best not only fits underneath your vehicle smoothly but also can easily handle your vehicle's full weight. For example, a tiny economy-sized car or roadster can be lifted by a less heavy-duty jack than can a full-sized SUV. However, the SUV can accommodate a much taller jack underneath it.
In the case of most passenger sedans and coupes, the best car jack for your vehicle is one that can lift at least two vehicular tons. If you have a large pickup truck or an SUV, the best car jack for you is one that can lift that heavier weight. If you need to jack up a recreational trailer, RV or an even larger vehicle, even greater capacity is needed. For example, certain farm machinery requires a specialized jack that's capable of lifting 10 tons of weight.
For maximum safety and peace of mind, open your vehicle's driver-side front door and find its informational decal. This sticker is usually found on the door itself or on the jamb. Check the measurement for the vehicle's weight, usually given as "Curb Weight," "Gross Vehicle Weight" or "GVW." Now you can shop confidently, knowing that the best car jack purchase to make is one that will support no less than the weight you read from the sticker.
Weight is not the only consideration when it comes to choosing among different types of car jacks. Even if they can hoist the weight you need them to, buy car jacks only when you are sure they can fit easily under your vehicle when it's parked. Here again, a regular sedan or coupe has low clearance, whereas most larger vehicles such as SUVs, trucks and RVs have significantly higher clearance.
Fortunately, car jack dimensions have been designed to take this into account. You can find top rated car jacks in low-profile designs that are no problem to position under a typical passenger sedan and can lift its weight easily. You also can find car jack designs that take advantage of the higher clearance often found on heavier vehicles.
For example, some car jack brands offer a bottle-jack design. Not only do these taller jack types fit well underneath an SUV or truck, but the bottle-style car jack designs are also capable of lifting substantially more weight. Additional designs are available to handle specialized vehicle-lifting needs. For example, trailer jacks are built to smoothly lift your recreational or other type of trailer without damaging its underside. Knowing this will help you decide which car jack to buy.
>> How frequently do you expect to use your jack?
The best car jack choice for you also depends on how often you expect to use your new purchase. If you love to work on your own or others' vehicles, your automotive supplies kit needs the right choice of floor jacks to be complete. You're also going to use your new car jack much more regularly than someone who only expects to need a jack for emergencies.
If you're one of those who is likely to use a jack frequently, look for a car jack design that has casters for easy maneuvering. An agile jack design can simplify the process of finding and hitting the right spots for lifting on a vehicle's undercarriage, saving you time and hassle. For frequent use, it's also worth investing in a model with a sturdy handle that moves the jack around effectively and offers a good grip. The heavier the jack, the more use you'll get out of a handle. Some jacks even have detachable handles, which offer a nice option for keeping the handle out from underfoot once the vehicle is lifted.
If you don't expect to use a jack often, a handle, casters and the overall maneuverability of your car jack design are probably less important. Just keep in mind that these are still useful features to have and can potentially get you back on the road sooner.
>> Think about finding packages
car jack design
Several brands offer good car jack deals in the form of combo packs. These often include equipment such as a creeper, which helps you slide under the lifted vehicle. Whether your new car jack comes with a creeper or not, anyone who frequently works under cars lifted on jacks usually finds that a creeper is handy to have around. It may be worth purchasing one separately.
>> Consider the different lifting mechanisms
No matter how frequently you expect to use your new car jack, there are two major jack mechanisms to know. Some car jack designs use hydraulic fluid to lift the vehicle, and others use a screw mechanism.
The screw design is often thought of as a manual jack. These types of jacks require significantly more energy from the user to lift a car. However, screw-type jacks are the most economical. If you do not expect to use your jack often, you may feel that the cost savings of buying a screw-type jack is worth that extra sweat on the rare occasions that you need to use it.
Hydraulic jacks are also referred to as pump jacks. On the one hand, these are much easier to use and require comparatively little effort to raise a vehicle to the desired height. On the other hand, they are often more expensive than their screw-type counterparts, although some purchasers feel that even for only emergency use, the reduced hassle of hydraulic car jacks is worth their extra expense.
>> Should you replace the jack your vehicle carries?
If your budget allows, it's often a good idea to replace the jack that came with your car's spare tire. The typical scissor-type jack that comes with your car may be sufficient for a quick roadside fix, but for any work beyond that, a model with more features is easier on you. Most car jacks you can purchase are sturdier and easier to use than the one your vehicle's manufacturer supplies.
Look for aluminum floor jacks when you're ready to replace the jack you routinely carry in your car. These are strong yet lightweight, which is important for a jack whose weight you'll carry on every trip, even to the grocery store. When you are deciding which car jack to buy, keep this in mind.
Many factors go into deciding on the best car jack for your needs. In a nutshell, they come down to understanding your vehicle's dimensions as well as your expected usage of your new car jack. Stay aware of jack safety, as well, and enjoy the smooth lifting power you're about to have.
A jack is a mechanical device used as a lifting device to lift heavy loads or apply great forces. A mechanical jack employs a screw thread for lifting heavy equipment. The most common form is a car jack, floor jack or garage jack which lifts vehicles so that maintenance can be performed. Mechanical jacks are usually rated for a maximum lifting capacity (for example, 1.5 tons or 3 tons). More powerful jacks use hydraulic power to provide more lift over greater distances and can be rated for many tons of load.
Jackscrew
Scissor car jacks usually use mechanical advantage to allow a human to lift a vehicle by manual force alone. The jack shown at the right is made for a modern vehicle and the notch fits into a hard point on a unibody. Earlier versions have a platform to lift on a vehicle's frame or axle.
Jackscrews are integral to the scissor jack, one of the simplest kinds of car jack still used.
Electrically operated car scissor jacks are powered by 12 volt electricity supplied directly from the car's cigarette lighter receptacle. The electrical energy is used to power these car jacks to raise and lower automatically. Electric jacks require less effort from the motorist for operation.[1]
House jack
2.5-ton house jack that stands 24 inches from top to bottom fully threaded out
A house jack, also called a screw jack, is a mechanical device primarily used to lift buildings from their foundations for repairs or relocation. A series of jacks is used and then wood cribbing temporarily supports the structure. This process is repeated until the desired height is reached. The house jack can be used for jacking carrying beams that have settled or for installing new structural beams. On the top of the jack is a cast iron circular pad that the jacking post rests on. This pad moves independently of the house jack so that it does not turn as the acme-threaded rod is turned with a metal rod. This piece tilts very slightly, but not enough to render the post dangerously out of plumb.
Hydraulic jack
Hydraulic jacks are typically used for shop work, rather than as an emergency jack to be carried with the vehicle. Use of jacks not designed for a specific vehicle requires more than the usual care in selecting ground conditions, the jacking point on the vehicle, and to ensure stability when the jack is extended. Hydraulic jacks are often used to lift elevators in low and medium rise buildings.
A hydraulic jack uses a fluid, which is incompressible, that is forced into a cylinder by a pump plunger. Oil is used since it is self lubricating and stable. When the plunger pulls back, it draws oil out of the reservoir through a suction check valve into the pump chamber. When the plunger moves forward, it pushes the oil through a discharge check valve into the cylinder. The suction valve ball is within the chamber and opens with each draw of the plunger. The discharge valve ball is outside the chamber and opens when the oil is pushed into the cylinder. At this point the suction ball within the chamber is forced shut and oil pressure builds in the cylinder.
In a floor jack (aka 'trolley jack') a horizontal piston pushes on the short end of a bellcrank, with the long arm providing the vertical motion to a lifting pad, kept horizontal with a horizontal linkage. Floor jacks usually include castors and wheels, allowing compensation for the arc taken by the lifting pad. This mechanism provide a low profile when collapsed, for easy maneuvering underneath the vehicle, while allowing considerable extension. Richard Dudgeon, Inc. was founded in New York City as a machine shop. In 1851, founder and inventor Richard Dudgeon was granted a patent for a "portable hydraulic press" - the hydraulic jack, a jack which proved to be vastly superior to the screw jacks in use at the time.
Bottle jack
A bottle jack or whiskey jack[2] is a hydraulic jack which resembles a bottle in shape, having a cylindrical body and a neck, from which the hydraulic ram emerges. In a bottle jack the piston is vertical and directly supports a bearing pad that contacts the object being lifted. With a single action piston the lift is somewhat less than twice the collapsed height of the jack, making it suitable only for vehicles with a relatively high clearance. For lifting structures such as houses the hydraulic interconnection of multiple vertical jacks through valves enables the even distribution of forces while enabling close control of the lift.
They have a capacity of up to 50 tons and may be used to lift a variety of objects. Typical uses include the repair of automobiles and house foundations. Larger, heavy-duty models may be known as a barrel jack.[3]
This type of jack is best used for short vertical lifts.[4] Blocks may be used to repeat the operation when a greater amount of elevation is required.[5]
Pneumatic jack
A pneumatic jack is a hydraulic jack that is actuated by compressed air - for example, air from a compressor - instead of human work. This eliminates the need for the user to actuate the hydraulic mechanism, saving effort and potentially increasing speed. Sometimes, such jacks are also able to be operated by the normal hydraulic actuation method, thereby retaining functionality, even if a source of compressed air is not available.
Strand jack[edit]
A strand jack is a specialized hydraulic jack that grips steel cables; often used in concert, strand jacks can lift hundreds of tons and are used in engineering and construction.
Farm jack
A farm jack attached to a vehicle
The farm jack is also known as a Hi-Lift Jack. The farm jack, invented in 1905 consists of a steel beam with a series of equally spaced holes along its length, and a hand operated mechanism which can be moved from one end of the beam to the other through the use of a pair of climbing pins. Typical sizes for the farm jack are 4 feet (1.2 m), 5 feet (1.5 m)and 6 feet (1.8 m) referring to the length of the beam.
The jack's versatility stems from its use for such applications as lifting, winching, clamping, pulling and pushing. It is this versatility, along with the long travel it offers and its relative portability, which make the farm jack so popular with off-road drivers.
Safety standards
National and international standards have been developed to standardize the safety and performance requirements for jacks and other lifting devices. Selection of the standard is an agreement between the purchaser and the manufacturer, and has some significance in the design of the jack. In the United States, ASME has developed the Safety Standard for Portable Automotive Service Equipment, last revised in 2014, including requirements for hydraulic hand jacks, transmission jacks, emergency tire changing jacks, service jacks, fork lift jacks, and other lifting devices.[6]
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