# Safety Warning: Scissors Jack Failure



## 92 Sinatra (Jul 9, 2002)

I have never heard of this happening before--and neither have any of my friends, and neither have any of the guys at the dealership, who offered to order me a new one for $60--but on Saturday I demonstrated that it can occur. So be careful!

The stock scissors jack in my '92 Sentra failed. Didn't topple over, didn't slip, didn't budge--it failed. I mean it collapsed. Gave it up & went straight down under load. As in having the car jacked up for a repair on a level concrete surface, ready to put a jackstand under the frame (since you never want to get under a car unless it is supported on jackstands or ramps, and even then you don't want to trust it too much unless you enjoy joking with your life), and the threaded rod goes ZIP! all the way out the hardened steel fitting on the end of the jack it had screwed through.

The jack had gotten sort of stiff, so before this incident I'd spent a while spinning it after putting fresh grease on the threaded rod, making sure it was free & wiping off the excess grease. It was still binding slightly on the way up, too--but I hardly expected this.

So anyway, folks--even if you take every precaution, be aware that this can happen. If the jack had decided to let go 15-20 seconds later, one of several things might've happened:
1. Since I always make sure the jackstand is the first thing that goes under the car (before any part of my torso) when I have the car jacked up, the car would've been supported on the jackstand someplace other than where I intended it to be supported. The weight of the car might have broken and/or bent something--plus getting the jackstand out from under there would have been a real hassle.
2. Before I had the jackstand set, the weight of the car coming down might've forced the jackstand to move violently in one direction or another. Odds are pretty good it would have come after my face.
3. Despite my mania for safety, I might've gotten my shoulder(s)/ribcage/head crushed.

At the time I was really hacked off because I couldn't complete the job. Now I figure it can wait until Saturday.


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## myoung (Apr 15, 2002)

A good reason to invest in a floor jack....


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## 92 Sinatra (Jul 9, 2002)

Yeah. . .but even a floor jack (hydraulic or otherwise) can fail. I never like to get under a car unless I've got it secure (!) on stands and/or ramps. Even then you have to respect all that mass.


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## sno (Oct 4, 2002)

that's why it's good to ALWAYS use jack stands.


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## niky (Jul 20, 2002)

yup... and I agree... hydraulic jacks are better... the kit I got with my sentra was all POS... my wrenches bent out of shape THE FIRST TIME I used them... I've dumped all my stock tools for real stuff.


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## sno (Oct 4, 2002)

niky said:


> *my wrenches bent out of shape THE FIRST TIME I used them... *


lol, mine too. you should see my oem lug wrench. it's so bent and twisted it's not usable anymore.


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## 92 Sinatra (Jul 9, 2002)

*Advantage of a quad wrench*

I've used the stock lug wrench once (way out on the road in an emergency), but around my place I like a good old American quad wrench. Makes a man feel like a genuine grease monkey spinning that thing.

As far as a scissors jack to keep in the trunk. . .do they make a hydraulic one that'll fit in the stock space? Not that I know of. I'll skip the dealership model at $60 & see about one from a salvage yard for $5-10.


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## niky (Jul 20, 2002)

With that tiny clamp put in for the stock scissors, I don't see any hydraulic going in there, except the stump ones... and i'd rather have an alligator than a stump.


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## 92 Sinatra (Jul 9, 2002)

*John Wayne re honor*

He said "Better inner than honor."


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## Fast91SER (Jul 2, 2002)

That happened to my stock jack in my sentra, ever since then I got a hydraulic jack I take with me everywhere I go (even the track lol)


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## BeEleven (Jan 22, 2003)

If you get a hydraulic jack and lift the car, then put the jackstand right next to the jack...then slowly let down the jack until the car contacts the jackstand...that way, you have about 50/50 weight distribution between the two supports, and if one fails, the car wont "fall" onto the other (thereby decreasing the force of impact)


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## toolapcfan (Jul 10, 2002)

That's fucking scarey. My gandpa had to help a neighbor lift a car off his dead son once. Also, don't put your car up on four jackstands if possible. I did that a couple times and damn near had my car fall off into my garage pole once. Always try to keep two on the ground, or use blocks of wood on one end that the wheels are set on. I don't trust ramps they're too flimsy. As for jacks, I say toss your factory one and get one of the small floor jack types that come in a plastic case for $20 and velcro it to your trunk carpet. It'd be nice if someone made folding jack stands that were light and inexpensive, you could keep a pair in the trunk. Now by folding I mean, the legs wouldn't bear the weight, just keep a pedastal upright, so there really wouldn't be any risk of it folding up on you and tipping over or collapsing.


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## 95 SentraB13 (Jun 14, 2002)

I usually do what BeEleven said above. I don't really trust being under the car with only one sole means of support. Even when I'm taking a tire off the first thing I do is place it somewhere underneath so if the jack were to fail at least the car would be stopped by the wheel instead of hitting the ground or hurting me.

Just a lesson from last week when fixing my crank seal; when you jack the car up make sure the hand brake is on and the rear wheels are blocked to prevent the car from rolling forward. I had my scissor jack on top a piece of 4x4" while turning away with my hand held 1/4" driver and long extension placed through the jack hole instead of using the absurd hook rod. Well, before the car was raised high enough to place the jack stand underneath it rolled forward and the first thing that went through my mind is "oh great, I'm going to get hurt some how". The jack stopped at a 45° angle which didn't make a lot of sense until the sound of the front tire contacting the ground registered in my head.


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## MomoB12 (Jul 22, 2003)

My dad once used some cheap ass bricks to hold a boat hauler (I don't know if that's the name... It's the thing you put a boat on and pull it with your car ) we used to have, and with the boat on it. I was really confused, since my dad never does anything stupid! I told him; "Those bricks look a lot less denser than normal ones" and all he said was "Naw, they're fine". Once he go out of the underbelly of the boat, BOOOOOOM!!! The bricks fuggin' exploded!!!! They didn't break in two, or three, they just blew up into dust!!! The trailer/hauler/boat puliing thingamajig would have landed right on my dad's stomach.
All he did was look at me. He didn't say nothing.

All I could see in his eyes was "That was f'in stupid.. Sorry for not listening to you"

Jacks stands go around 10 bucks each here. I don't have them... So I use two 2-ton hydraulic jacks, just like Beleven.


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## niky (Jul 20, 2002)

In absence of jack stands, 95 SentraB13 is right... the spare is the best security.


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## 92 Sinatra (Jul 9, 2002)

Well, I'm glad that this thread has sparked a lively discussion focused on safety. Lots of people take the things they work on for granted & never consider that "Hey! If I screw this up, it could kill me!"

Or worse.

I've always done my best to ensure that I didn't rely on any one means of support; however, when this incident occurred, it was just before that 3-4 second interval when I was going to slide the jackstand under there, then let the jack down a bit to share the load.

I also agree that you'd better be damned careful about bringing all 4 wheels off the ground (up on jackstands or whatever). A car is massive as hell, but if you get the fulcrum in the right place, you can easily pivot more than a ton by pressing one finger laterally. That can be bad mojo.

Other basic tips that are easy to overlook (forgive me if this seems overly obvious; let me know if you can contribute more):
1. You're always safest on a level surface.
2. Clean & level concrete is the surface of choice. Asphalt can cave in just like dirt or gravel, depending on what's beneath it.
3. Unfortunately wheel chocks are virtually useless on concrete unless you get some of the car's weight bearing on them. Even then they can slip out of there unexpectedly. I have a friend who used a masonry bit to drill some holes in his garage floor, and when he uses wheel chocks he puts these big hairy 6-inch bolts in the floor for the chocks to press against


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## nastynissan (Jan 26, 2003)

IF youve got to have a scissor jack in the car..... Id go to the JY and pick up an older (90 and earlier) scissor.... Ive lifted some NASTY weight with the older ones and they keep going..... Personally I keep a Cheap floor jack and 1 jackstand in the trunk.,... JUST IN CASE...


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## BikerFry (Jul 31, 2003)

I was workin on my 92 F150 last summer and had one of the back corners supported by my jack sitting on a cinder block. I was changin the drums and shoes when the damn cinder block crumbled and the thing fell over. I wasn't even under the thing but it scared me so much seein 2 tons of steel fallin in my general direction that by the time the thing hit the ground I was halfway across my front yard. To think that, between shocks, exhaust, fuel lines, and a leaky oil pan that couldn't be swapped without pullin the motor, I spent half my summer underneath that thing. Gives me the chills... When it comes to supporting a vehicle you're about to crawl under, go for overkill.

On a lighter note, I shoulda just gone for the cinder blocks and no jack. The ******** in my town support cars for years that way right their front lawns!


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## PEZ (Jan 27, 2020)

My boyfriend was changing my tire (2014 Nissan Juke) with the stock kit and scissor jack. No problems. Got the tire off. My Juke was parked in front of his Chevy Impala with about 1-2 ft between them. Now, I know I shouldn’t have walked between the cars. But the emergency brake was on. The jack was in the niche. The car was in park. I didn’t touch the car. And as just cleared the fender, the jack failed. The Juke came crashing down and back into the Impala. My boyfriend was incredulous. He had never seen anything like it. Jack on the ground with concrete scrapings where it had been forced against the driveway. I just stood there in shock for a good 10 seconds or so until I finally heard him calling my name. It didn’t escape either of us that I was one second away from having been crushed between those two cars.


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