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Almost any mechanical job you might tackle may require that you are able to safely jack the effected vehicle to a position where you can either:  access components under the vehicle, remove one or more wheel(s), raise the vehicle to lower vehicle components when otherwise impossible (ie. transmission).  This how-to article aims to help illustrate proper vehicle jacking procedures.

Tools / Resources: Consumables:
  • floor jack
  • 1 or 2 set(s) of jack stands
  • 4 x wheel chocks
  • N/A

As a disclaimer, we always recommend that you read your vehicle's manual (or better yet - the factory workshop manual) before attempting any service items.  In this how to, you will be required to know and identify the factory approved "jack points".  Typically, these points can be found under "Emergency" in the vehicle operator's manual.

Because of the dangers of having a 1000+ kg vehicle looming over you as you work, we will accept absolutely no responsibility for any accidents that may occur while you service your vehicle.  Safety is everybody's responsibility - the following article will attempt to reinforce this concept.

Before you buy jack-stands, and a floor jack be sure that each component is strong enough to support at least half of the vehicle's "curb weight".  DO NOT take chances here!

As safety is a major focal point of this write up, all steps will have some proximity to safe practices - the first step is a subtle example.

Before you consider jacking up a vehicle, find as flat / level a work area as possible.  This is essential as you do not want to have a vehicle leaning while up on jack stands.

If you can not find a nearly level work area, do not attempt to jack the vehicle up!

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Once your safe jacking position is secured, move the vehicle into position.  Start by chocking the wheels of the un-effected axle.  That is to say, you should place cinder blocks, 4 x 4 blocks, or similar large wedges in front and behind the wheels which will remain on the ground during the initial jacking process.

If you are jacking the front of the vehicle up first, be sure to apply the parking brake in conjunction to chocking the rear-wheels.  If the vehicle is rear-wheel drive, place the vehicle into 2nd gear.

If you are jacking the rear of the vehicle, be sure to chock the front wheels.  Furthermore, if the vehicle is front-wheel drive, put the vehicle into reverse gear (or park in the case of an automatic).

The basic concept with chocking + locking the wheels (brakes) is to prevent the vehicle from shifting or rolling during the jacking procedure and through out the entire service procedure.

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Once you have prevented the vehicle from rolling forwards or backwards, and you are confident that the plot of workspace you have chosen is level, position the floor jack in the approved factory location.

Be sure to place the jack in an accessible location, free of interference with any vehicle chassis parts.  Double check that you are positioning the jack in a factory approved area as the vehicle's weight will be centered on the jacking point.

In our example, the vehicle we are using in this "how to" is a RWD (rear-wheel drive) Mazda MX-5 Miata.  The factory approved jacking points are as follows:
  • rear differential housing

also referred to as the "pumpkin"

  • front cross-member

    just in front of the oil pan

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As a tip, when working on a soft-surface workspace such as an asphalt driveway, we recommend that you place 1/4" or thicker MDFB (medium density fiber board) or plywood under the floor jack and jack-stands to spread the weight of the vehicle over a larger footprint to avoid ruining the surface.

Failure to protect your working surface from extremely localized pressures can irreversibly damage the wearing surface, costing you quite a bit more in the long run than a 4' x 4' piece of 1/2" plywood.

Begin jacking the vehicle up using the floor jack.  Be very cautious whilst raising the vehicle - watch for shifting, damage to the jacking-point(s), and any other points of concern.

This is where most accidents occur .. so as mentioned, take your time and always think safety!

Do not position yourself under the vehicle where your limbs or torso are prone to being crushed should the vehicle slip from the jack.  If you really must put yourself in harm's way in order to jack up the vehicle, you are doing something wrong.

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Once the vehicle is raised sufficiently, place the jack-stands under the factory approved jacking points.  In the case of our Miata, they are the reinforced "jacking points" [these "jacking points" are only good for the emergency "scissor" type jack and should not be used with the floor jack.

The jacking points are emphasized by two "notches" in the metal along the underside of the vehicle chassis.

If you can not see the jacking point from the near-side of the vehicle, here is another perspective (looking across the vehicle under-belly).

The factory jacking point is the space between the arrows.  Once again, do not use a floor jack on these points as they will likely be bent and distorted - these jacking points are only designed for the scissor type jack. They are however acceptable jack stand points.

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Be sure to always use a minimum of two jack-stands when raising the front or rear of a vehicle - that is to say that you should never have a vehicle tilted up only on one corner as though you are installing the emergency spare tire.  Doing so will have yourself, your immediate family, and extended family killed by the car gods.  No really, it's that bad an idea.
Once the jack-stands are in place, you may slowly lower the vehicle onto the jack-stands.  Be sure to watch both jack-stands for interference by chassis parts, etc .. and if you run into problems, jack the vehicle back up and re-position or re-plan your jacking sequence.

You may need to re-position the jack stands during this procedure so be sure to lower the vehicle under control at all times.  If you need to adjust the jack stand positions, do not do so from under the vehicle's crush zones (ie, any place where you or your limbs would be crushed if you were to lower the car).

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Once the jack-stands take up the vehicle's weight, stop lowering the jack and raise it back up one "notch".  Think of the floor jack as an extra insurance policy - if the jack-stands somehow fail, you have at least one chunk of metal preventing you from becoming raspberry jam.

If you can not leave the jack in the factory approved jacking location, consider moving it to another location.  If you must move the jack, position it under the vehicle's frame but do not raise the jack foot to press against the frame - just leave it in position as a backup.

Once you are confident that the vehicle has been safely supported by the jack and jack-stands, take a step back and examine everything.  Never blindly jack up a vehicle and immediately crawl under it.

Once you have double-checked everything, give the vehicle a slight nudge to ensure that the forces you will exert during your mechanical procedures will not cause the vehicle to become unstable and fall off the jack-stands thus killing yourself, your immediate family, and extended family as noted above.

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Once you are satisfied that you have done everything in your power to make the worksite as safe as possible, you have completed that jacking up of your vehicle.  Congratulations!

When dealing with workspace safety, it is always good to be more prepared than necessary - never overlook the importance of safety!

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