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I just had to put a doughnut on my car and I used the typical manufacturer car jack that fits into that little slot of metal near your wheel. After I got all the lug nuts out, I tried pulling the wheel off in several different ways with all my strength and it was still stuck, so I went under the car and kicked off the tire and it fell to the ground.

I wouldn't think this is a safety issue because you got a ton of weight sturdily mounted onto the jack, but I really hate those jacks that you have to crank with your hand that seems to come with all cars. I want to get one of those jacks that you can pump and release, jacking your car with one of those is really easy and takes like 10 seconds or less.

Do I have anything to be concerned with here if I go this route? Being crushed by a car is not how I want to spend my future!

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    Thank you for using the term "donut" to refer to a spare tire. I used that word at a tire store some years ago and they stared at me as though a new limb had spontaneously erupted from my forehead. (That is, they had no idea what the word meant). I've been silently unsure of my use of the term since...until now!
    – bvoyelr
    Commented May 11, 2018 at 16:16
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    For a stuck tire, you don't need to kick it from under the car. Stand with your back to the car and "donkey kick" the bottom sidewall of the tire, turn the tire 90 or 180 degrees and repeat. I've done this successfully dozens of times, its effective and much safer.
    – Dan
    Commented May 11, 2018 at 18:36
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    I've had 3 scissor jacks collapse while being used, all for the car they were provided with (mostly due to age/no maintenance). Once the jack collapsed while I was under the car (luckily I had jack stands in place). Don't ever trust a jack, if I have to get under the car, I have 2 jack stands and test them before getting under (jack stands can fail/tip too).
    – Ron Beyer
    Commented May 11, 2018 at 20:25
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    For the people who think this is not plausible, I have a friend who did this, too... And now he has to listen to the story at every gathering, "remember that time [name redacted] was silly enough to get under the car and kick the tire?!!" Commented May 12, 2018 at 18:06
  • 17
    One of my neighbours died this way about 25 years ago. He was about 19 years old, 2 houses away. Commented May 14, 2018 at 8:22

12 Answers 12

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The ONLY time you should crawl under a car is when it is supported by a jack stand or on a lift. A jack is used to jack the car up and let it down. It is a huge safety concern to use it to support the car while crawling under it. You can kick the tire from the outside of the car if it won't come off, but keep your body parts away from underneath the car. When a jack lets go it does it in a hurry, without notice, and without provocation. Use it only to temporarily suspend the vehicle when needed, but nothing else.

EDIT: As a commenter pointed out, differentiating between a "jack" and a "jack stand" may be beneficial to the uninitiated. To that end, here are some pics and explanation.

Scissor Jack

Scissor Jack image sourced from Walmart website.

Typical scissor jack which is used on a lot of vehicles as OEM equipment from the factory. While scissor jacks vary in size and shape, it should be noticed the small base and head, which do not lend well to stability. They are small so they can be stored in a small space. Other jack types may be used as an OEM for changing tires in an emergency, but they will almost always be small and overall have stability issues. This should not be used to keep the vehicle supported, but rather for lifting and lower the vehicle.

Jack Stand

Jack Stand image sourced from Walmart website.

Typical jack stand which is used to support vehicles for a more lengthy amount of time and where safety is a concern. Jack stands will vary in size, shape, and amount they can support, they will almost always have a wide base to make them stable while supporting a vehicle. This doesn't make them perfect, but when used properly, there should be no fear while crawling under a vehicle. Notice, the positive locking support near the head which allows for height adjustablility. As long as this is locked into place correctly, there is very little to fear about failure during use.

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    @Katz_Katz_Katz - It isn't a bad idea. I didn't say you shouldn't kick the tire, it's just you shouldn't do it from under the car. Sitting on the ground with one foot to each side of the tire kicking it is not very glamorous, but it is pretty effective ;-) Commented May 11, 2018 at 0:33
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    A dead-blow type hammer on the RIM will work much better. If no hammer is available (and the tire is not flat), you can loosen the lug nuts 2 turns each, and drive the car slowly (<10mph) and jam on the brakes. You may need to repeat several times and change directions. At some point it would be good insurance to smear a light coat of anti-sieze or thick grease in between the rim and the hub contact surface. I'd do it on all four wheels.
    – SteveRacer
    Commented May 11, 2018 at 2:51
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    This is especially helpful with modern aluminum rims in contact with cast iron or steel hub surfaces - it prevents the galvanic rusting and "welding" for the next time the wheel(s) have to come off.
    – SteveRacer
    Commented May 11, 2018 at 2:51
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    This answer is treating Jack and Jack Stand differently without defining their difference. I submit that the kind of people that need to be told about this safety concern likely need to be told the difference between Jacks and Jack Stands. Commented May 11, 2018 at 14:12
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    What's important with a jack stand is not only the base, but also the fact that jack stands are constructed so that they can't be lowered with the weight of the vehicle on them. If a vehicle is on a jack stand, lowering the stand will require first jacking the vehicle up off the stand--something that isn't apt to happen by accident.
    – supercat
    Commented May 15, 2018 at 15:02
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Yes, you do have something to worry about. Even with a lot of weight on a jack, the jack could move, either back and forth, or side to side, and the whole shebang could pivot down until the car rests on the ground.

Hydraulic jacks are indeed easier to use, but even they can fail. Would you like to be lying underneath when one of the hydraulic seals lets go and the jack collapses?

It's a poor idea to put any part of your body under a car resting on any kind of jack. If you're going under a car, the car should be held by jackstands or sturdy supports that can't collapse, can't pivot, and can't move.

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    A friend of mine lost a friend to a collapsing hydraulic jack under a truck, ANY jack can fail, you MUST use axle stands or something else SOLID and IMMOVABLE under a vehicle if you're going to get under it. I lay the spare tyre or other large object underneath if there's nothing else, just to ensure it can't fall ALL the way.
    – John U
    Commented May 11, 2018 at 14:35
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What you did was dangerous, there are Darwin Awards for just this type of thing! The likelihood of something going wrong is low, but the consequences are terrible if it does. There are many failure modes when jacking up a car: Scissor jacks are pretty reliable but they can fail, the ground could be unstable or the surface could collapse due to the weight. I've had a jack point collapse due to hidden corrosion one time, went right through the body of the car that looked completely solid!

Even if nothing physically fails a jack can slip if it's not positioned right, say it's off center from where it should be, kicking the tire may move the car just enough to bring the car down.

I keep a lump hammer (a short handled hammer with a big, heavy head) in my trunk just for this type of event, but there are a few tricks you can try if you don't have one:

  • Loosen the nuts on the wheel a bit then drive the car forward and backward slowly, you can try driving slowly into a kerb as well
  • Hitting the tire with the tire iron over and over. It doesn't sound like much but it works remarkably often
  • Hitting the outside edge of the tire with the heel of your hand over and over. Again, it doesn't sound like much but I've had good success
  • Although it's already been mentioned kicking the tire works well, and would be the first thing to try, obviously not from underneath the car. Kicking the outer edge of the tire gives the most leverage as it's farthest from the hub. Lying flat on your back and kicking with your heel gives you a lot of power, if the tire comes off it may fall on your legs though. Kicking while standing is not something I'd recommend if you're close to traffic as losing your balance may cause you to stumble into the road, which is bad™
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    Never mind your hand - a good boot on the tyre will do the job. The hub on one side acts as a fulcrum, so the other side of the tyre pushes out. And you can administer the boot whilst stood next to the car, not lying underneath it.
    – Graham
    Commented May 11, 2018 at 9:43
  • Absolutely @Graham, I didn't list it as the OP already mentions it, but the old size 11 would be the first thing I'd try. You can get a lot of leverage lying on the ground kicking the edge of the tire, the only drawback to that is if it comes off it may fall on your legs. I'll add it in for completeness.
    – GdD
    Commented May 11, 2018 at 10:03
  • That DA is almost too good to be true...
    – AnoE
    Commented May 14, 2018 at 22:03
  • Boot from the outside might be worth trying first if you can do it safely (but there's always the risk of dropping the car off the jack which can get expensive), but out of all the stuck tires I've had it's only worked a couple of times. Loosening the lugnuts and driving has never helped any of them I've had either. Call for a tow to be safe. Commented May 15, 2018 at 14:59
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Assuming you had to do this on the road (why else would you want to put a donut on?), I wouldn't go under the car no matter how steady it is, even on a jack stand on a completely flat patch of concrete. In case someone crashes into your car, you're toast. In case of a car jack, it could be enough for a big vehicle to drive close to your car and blow it out of the equilibrium with the wind it creates.

Remember that roadside is a very unsafe place (that's why you have to wear that safety jacket and put the emergency triangle out), and don't do any repairs there that won't let you see incoming traffic or jump to safety if need be.

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  • What safety jacket and emergency triangle? Do you carry those in your car? I've never thought about buying those things to keep in my car. Is that something that is commonly done?
    – user37640
    Commented May 14, 2018 at 17:12
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    Carrying a safety vest and triangles is only common in the US if you're driving a commercial vehicle. Other countries may have different rules. Regardless of the rules, it's a good idea for anyone. Commented May 14, 2018 at 17:59
  • Carrying (and deploying) a triangle is mandatory in e.g. Germany. Carrying (and wearing) a safety vest is mandatory in e.g. Austria.
    – AnoE
    Commented May 14, 2018 at 22:01
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    Safety triangles are inexpensive. So are safety vests (think I paid about $6 including shipping on eBay recently). Especially compared to a hospital (or morgue) stay. Commented May 16, 2018 at 0:20
  • @user128216 Yeah, I didn't know those weren't required in US. Anyway, I just mentioned these to reinforce the idea about roadside repairs being dangerous, especially when going under the car. Commented May 17, 2018 at 11:43
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Even if you had supported the car properly with jack stands, it was still a huge mistake to kick it or exert force on it. Even jack stands are not so stable that they can handle a lot of dynamic side-load. This was a very foolish thing to do.

What made this even worse is you were under the car. There's an old saying about the risks of being killed by a falling coconut: there are statistics, but the important part is everyone who got hit by a coconut was standing under a coconut tree at the time! Same can be said about getting hit by a train - you can't get hit by a train if you don't put yourself in train tracks unawares!

I've done the job you just did, and you didn't need to be under the car to do it. Seriously. If you must kick it, do the coconut trick - position yourself so the car can't fall on you. Kicking the tire inward on one side will make the other side pop out. Another way is to put the lugnuts back on, back them off 1-2 turns so they're sloppy, let it down and listen for the pop. No pop, drive 2 feet. The weight of the car will break the wheel loose!

You might also take a hard look at whatever sense of invincibility/immortality possessed you to do that. That sense is false, you are more fragile than you think.

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Never, EVER get under a car supported by a hydraulic jack alone. You MUST use jack stands (or something equivalent) or you are practically begging for a Darwin Award. Consider that if you use a hydraulic jack alone to support a car and then crawl under it, your life is now down to the quality of a 10 cent o-ring that was probably bought on the "low bid" by the jack manufacturer.

Mechanical jacks are arguably a little bit safer, but you still have to ask if you want to trust your life to one "single point of failure". And consider that even if the jack is mechanically sound, the car might roll, or shift sideways, if it's on an incline to any degree. Even a VERY slight incline can result in the car shifting sideways, causing the jack to topple.

There are many, many, many bad things that can happen if you get under a car that isn't properly supported. I would say never get under a car unless it's supported by something like a jackstand, or a substantial chunk of wood/metal/etc., AND the wheels are chocked (and/or the emergency brake is set). I'm redneck enough to accept a chunk of creosote post or a piece of an 8x8 beam or something instead of a purpose built jackstand, but don't trust just the jack alone.

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Don't hammer a rim... even a steel one can deform and then it is a bin job but an alloy is pretty easy to damage.

Frankly with a wheel stuck on there are a couple of less dodgy options (and if it is for changing a flat then pump it up first - they are rarely so flat they won't hold air for a bit)

  1. Put the wheel nuts in loose (enough to stop wheel falling off completely) and drive around over some bumps. This is less practical now the cheapskate manufacturers have stopped using studs and nuts and gone for the bolts which means you can no longer change the wheel in the dark. This will normally loosen the wheel and allow it to come off when you jack the car. No high-speed manouvering is suggested :)

  2. Take it to a tyre centre and enlist their help... I had an alloy fail to come off the iron centre once (they do corrode nicely together)... in the end car was on the ramp in the tyre place a couple of guys holding a large heavy wooden plank against the inside of the wheel and another with a 10lb sledge hammering the plank (rather than direct on the wheel or tyre to avoid damage)... yes, it did come off eventually but I certainly wouldn't expect it to come off by kicking from underneath and the first method didn't help, although it has worked on others.

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  • Don't do (1), it is both bad for the wheel and studs and totally unnecessary, and you don't need to do (2). Just get a jimmy bar and apply.
    – user207421
    Commented May 13, 2018 at 5:31
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    @EJP, clearly you've never has the misfortune of having a stuck wheel then. I've had to do #2 before. Even up on a hoist with plenty of room to maneuvre, it took 15 minutes with a sledge hammer on the end of a short piece of 2x4 against the inside of the rim to get each wheel off. There's no way a pry bar would have worked.
    – user37640
    Commented May 14, 2018 at 17:17
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I've pulled a car clean off a jack before. Just don't.

In many case the handbrake was stuck on (broken spring) and the ground wasn't great so as soon as the load on the jack was slightly off vertical it dug in and kept going down.

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  • A Jack is inherently unstable. It rolls, it has poor base, the wrong part of the car is often used as the contact / lift point. I can often cause a jack to fail with only moderate lateral force.
  • A jack stand, while better, is still not sufficient. It too can fail as can the part of the car to which it is attached. If you consider the moment arm of an extended jack stand, it really doesn't support much lateral force either.
  • Never, in automotive or other situations of potential peril, depend on a single point of failure (insomuch as it can be avoided). If you can't afford / access a lift, place a very strong and large object under the car such that a failure of your primary support will result in the car's fall being stopped by said object - vs. by you.

This question is so silly, I can't help think it is an attempt to get reputation. The worst part, I took the bait -- but only because someone may actually read this and decide to better protect themselves in the future.

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Never, ever, ever is it safe to be under any object that is supported by just a jack. Really, never.

To pop the tire off just loosen the lug nuts and rock the vehicle from the curb side, it will pop loose and all the dangerous gravity related problems like being crushed or flopping into traffic is pretty much eliminated.

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Kicking the car tire from underneath the car (or doing anything that might cause it to shake) is IMHO a bad idea whether it's on a jack or a jack-stand. And, as has already been noted, no one should be beneath a car while it's on a jack. They drummed this into me when I was a kid, along with things like don't put an electrical appliance on the edge of the bathtub.

I found a friend in a situation where kicking the tires didn't work. I was able to place the scissor jack from my car between the tire and a solid frame component and remove the wheel that way. Just be sure that the thing the jack is pushing against isn't deformed by the pressure.

0

If your tire is stuck, use your spare tire as a sledge hammer. Let it collide with full speed against your stuck tire (90 degrees angle). Since the new tire is quite heavy it will bounce back with full speed, and by repeating this a couple of times on both left and right side of the tire, the wheel won't be stuck anymore.

This will usually solve the problem but if it is still stuck, use a camping gas torch burner to heat the center a little bit and repeat the trick above!

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