A jack is a lifting tool, not a support tool
This is the single most important thing to understand about jacking a car up safely, and it’s the point most DIY accidents around car maintenance come back to. A jack, whether it’s a scissor jack from the boot or a proper trolley jack, is designed to lift a car, not to hold it up safely while someone works underneath. Jacks can fail, slip, or release unexpectedly for reasons that have nothing to do with using them incorrectly, hydraulic seals can fail, the ground beneath the jack can give slightly, or the jack simply isn’t rated for sustained load in the way axle stands are.
Axle stands, by contrast, are specifically designed to bear a car’s weight safely for an extended period while someone works beneath it. Once a car is raised to the height needed, the jack’s job is essentially done, and the axle stands take over holding the car’s weight securely, with the jack itself removed or at most left as a backup rather than the primary support.
This isn’t an overly cautious recommendation, it’s the difference between a genuinely safe working setup and one that carries a real risk of a car falling on someone. This article explains exactly why that risk is real, how to use axle stands correctly, and what other precautions matter when working underneath any vehicle.
How a jack can fail without warning
Hydraulic jacks rely on a seal holding pressure to keep the car raised, and seals degrade with age and use, sometimes failing suddenly rather than gradually. A jack that’s worked perfectly for years can develop a slow leak that only becomes apparent when it’s under load, at which point the car begins to lower, sometimes gradually and sometimes suddenly, depending on how the seal has failed.
Scissor jacks, the kind supplied with most cars for emergency roadside tyre changes, are designed for short-term use only, changing a wheel quickly at the roadside, not for sustained support while someone works underneath the vehicle for an extended period. Using one as a long-term support, rather than its intended purpose, significantly increases the risk of failure simply through being used well beyond its designed application.
Even a well-maintained, good quality jack can be undermined by external factors entirely outside the jack’s own condition, uneven or soft ground shifting slightly under the load, the car being nudged or rocked while raised, or the jack not being placed on a proper, stable jacking point in the first place. None of these failure modes require anything to be technically wrong with the jack itself.
Using axle stands correctly
Start by raising the car with the jack positioned at a proper manufacturer-specified jacking point, usually marked or reinforced points along the sill or chassis, never on bodywork or plastic trim that isn’t designed to bear weight. Raise the car to slightly above the height you’ll need, giving room to position the axle stands underneath.
Position axle stands at solid structural points, not the same point the jack is using necessarily, but somewhere the car’s structure can genuinely bear sustained weight, often specific reinforced points along the chassis rails. Lower the car gently onto the stands until its weight is fully resting on them, then give the car a firm shake or push to confirm it’s stable and secure before doing anything else.
Always use a matched pair of stands rated for your vehicle’s weight, never a single stand with the jack left supporting the other side, and never stack improvised supports, bricks, wood, or anything not specifically designed and rated for this purpose, since these can shift, crumble or fail under sustained load in ways a proper axle stand won’t.
Working surface and stability matter as much as the stands themselves
Axle stands are only as safe as the surface they’re placed on. A firm, level, solid surface, a proper concrete driveway or garage floor, is essential, since soft ground, gravel, grass, or an uneven surface can allow a stand to sink or tip slightly under load, undermining the stability the stand is meant to provide. Never attempt to jack a car up and work underneath it on a slope, softer ground, or any surface that isn’t genuinely flat and solid.
Check that the car’s handbrake is applied and the car is left in gear (or park for an automatic) before raising it, and consider using wheel chocks on the wheels remaining on the ground as an extra precaution against any unexpected movement. This matters even more if you’re only raising one end or one corner of the car rather than the whole vehicle, since the wheels still on the ground need to be properly secured against rolling.
If you’re working in a garage or driveway with any incline at all, however slight, it’s worth reconsidering the location entirely rather than assuming a small slope won’t matter, since even a modest gradient can be enough to compromise stability under the wrong circumstances.
What can go wrong and why it matters so much
If a car falls while someone is underneath it, even from a relatively modest height, the consequences can be genuinely severe, crush injuries, and in the worst cases, fatalities, which is why this particular safety measure isn’t one worth cutting corners on regardless of how confident you feel or how quick the job seems. Unlike many DIY mistakes that are inconvenient or costly to fix, this is one where the worst-case outcome is about as serious as it gets.
It’s also worth noting that many serious incidents involving jacks happen not during long, involved repairs but during quick jobs that felt too simple to warrant proper precautions, someone reaching underneath briefly to check something, assuming the jack alone would hold for just a moment. These “it’ll only take a second” moments are exactly when accidents happen, since the risk doesn’t reduce just because the intended time under the car is short.
Treat any time spent with any part of your body under a raised car, even briefly, as requiring proper axle stand support, without exception, regardless of how quick or simple the task feels at the time.
Ramps as an alternative for some jobs
For jobs that don’t need the car raised particularly high, oil changes being the classic example, drive-on ramps can be a safer and often more convenient alternative to jacking and stands. Ramps provide a stable platform the car’s wheels rest on directly, removing much of the risk associated with a jack and stand setup, provided the ramps themselves are used correctly and on a suitable surface.
Even with ramps, the same basic principles apply, use them on firm, level ground, apply the handbrake and chock the wheels remaining on the ground, and never assume a ramp is completely immune to movement without taking basic precautions. Ramps aren’t suitable for every job, particularly anything requiring you to be underneath a specific wheel that needs to be off the ground entirely, which is where proper axle stands remain the right tool.
Whichever method you use, the underlying principle stays the same: whatever’s supporting the car needs to be something specifically designed and rated for sustained load, not a tool designed only for the temporary act of lifting.
Other precautions worth taking underneath a car
Beyond the jack and stands themselves, a few other precautions matter when working underneath any vehicle. Disconnect the battery for anything involving electrical work, to avoid the risk of an accidental short circuit or unexpected component activation while you’re underneath. Let the car cool down properly before working underneath it if you’ve just been driving, since exhaust systems, engine components and brake discs can stay dangerously hot for a considerable time after use.
Wear eye protection if there’s any chance of debris, rust or fluid falling as you work, and keep a phone within reach in case you need to call for help, rather than leaving it out of reach on a workbench or in the house. It sounds like an obvious precaution, but it’s easy to overlook when focused on the job itself.
If you’re working alone, it’s worth letting someone know roughly what you’re doing and how long you expect to be, particularly for anything involving being underneath the car for an extended period, simply so someone would notice and check on you if something did go wrong.
Buying and maintaining your own axle stands
If you’re planning to do your own maintenance regularly, investing in a proper pair of axle stands rated for your vehicle’s weight is worthwhile, rather than relying purely on a jack or improvised supports. Check the weight rating printed on the stands against your vehicle’s actual weight, including any margin for safety, rather than assuming any stand will do for any car.
Inspect stands periodically for any damage, bent legs, a ratchet mechanism that doesn’t engage cleanly, or visible rust affecting structural integrity, and retire any stand showing signs of damage rather than continuing to use it and hoping it’s still safe. A stand that’s failed once, even partially, isn’t one to trust with your safety going forward.
Store stands somewhere dry to reduce rust risk, and keep them together with your jack so you’re never tempted to skip using them simply because they’re not immediately to hand when you need them.
When it’s simply not worth doing yourself
Some jobs require the car raised for an extended period, or require working underneath in a position that’s harder to do safely even with proper stands, and for these it’s worth honestly weighing whether the job is genuinely suited to a home driveway setup at all, however good your equipment. A proper garage lift removes the risks associated with jacks and stands entirely, and for more involved undercar work, this is often the safer, and sometimes ultimately cheaper, option once you account for the risk involved in doing it yourself.
If you’re ever unsure whether your setup, jack, stands, surface, is genuinely safe enough for a particular job, that uncertainty is itself a good reason to have a professional handle it instead. There’s no shame in recognising that a job’s beyond what your home setup can safely support, and it’s a far better outcome than finding out the hard way.
Getting undercar work done safely with SSK Mechanics
If a job needs your car raised and you’re not confident your home setup is genuinely safe for it, or you’d simply rather not take on that risk yourself, SSK Mechanics offers a Full Health Check and a wide range of undercar work across West Yorkshire and Bradford, using proper equipment designed specifically for safely raising and supporting vehicles during inspection and repair.
We come to your home or workplace, which means you get the benefit of proper equipment and trained handling without needing to invest in it yourself or take on the risk of an improvised setup. Book a Full Health Check with SSK Mechanics for peace of mind, whether that’s for a specific job you weren’t confident tackling yourself, or simply a thorough once-over to catch anything that needs attention before it becomes a bigger problem.
Teaching this properly if you’re showing someone else
If you’re introducing a partner, family member or friend to basic car maintenance, jacking and axle stand use is worth teaching properly and slowly rather than rushing through it as a formality before getting to the “real” job. Show them exactly where the correct jacking points are on their specific car, how to position axle stands correctly, and importantly, insist on the shake test every single time before anyone goes near the underside of the car.
It’s worth being honest that this is the one part of DIY car maintenance where cutting corners has genuinely serious consequences, unlike most other mistakes that are simply costly or inconvenient to put right. Building that understanding early, rather than treating axle stands as an optional extra step, sets a habit that matters for as long as someone continues doing their own maintenance.