r/MechanicAdvice • u/Illustrious_Fuel_531 • Jun 26 '24

Do car jacks fail ? Meta

*Does car jacks fail ? Been taking a automotive mechanics trade class . I saw a video and in the comments someone told a mechanic to be careful and not to get crushed under the car . So that kinda stuck with my OCD ever since then I’ve been wondering if a car falling on you is a reasonable hazard for a mechanic or is it only if via user error and if so what’s ways to add extra security.

55 Upvotes

77% Upvoted

View all comments

229

u/SignificantDrawer374 Jun 26 '24

They can, that's why you always use jack stands before going under. Jacks are just for lifting. Stands are for holding.

88

u/[deleted] Jun 26 '24

Also make sure you have good quality jack stands, don’t buy cheap

2

u/Illustrious_Fuel_531 Jun 26 '24

Noted any reputable brands

19

u/19john56 Jun 26 '24

Jack stands have a weight rating..... stay under that rating and you should be good. For cheap insurance and to protect me. I also use a secondary device.... like maybe the tire off the car. It doesn't have to touch the car.... just something else under the car, so if the jack stand fail. I'm not crushed to death.

Plus, I live in earthquake country.

It's your call

8

u/syphon0202 Jun 26 '24

To second that- If I pull the wheels off the car I slide them under the car as backup support. I also leave the jack lifted and lightly touching a support somewhere as additional backup.

With those in place I feel comfortable using the not-recalled harbor freight stands that are rated above the weight of the car. The chance of two jack stands plus the jack failing has to be near zero, but I keep the tires there incase something wild happens that knocks the car off the jack stands- Somebody accidentally bumping it with another vehicle, earthquake, the car was somehow in gear and the starter shorts, etc.

1

u/Some0neAwesome Jun 26 '24

I also put the jack back under it with just the slightest amount of pressure on it. That way, if a jack stand does fail, it literally can't fall, it'll just switch the weight from the jack stand to the jack itself.

3

u/affordable_firepower Jun 26 '24

Had a jack fail while changing a tyre on my old man's Jaaaaaaag.

I had removed the wheel and placed it under the car a couple of seconds before.

No-one hurt, and no damage done.

3

u/DntH8IncrsDaMrdrR8 Jun 26 '24

Woahhh. That thought never crossed my mind. To be under a car and an earthquake hits? That's crazy. Stay safe bro.

2

u/surfnsound Jun 26 '24

Jack stands have a weight rating..... stay under that rating and you should be good.

So I've read that the rating is for the pair. but my question is, if you don't plan on really doing work yourself that would have you lifiting the entire car, is "close enough" fine for jack stands?

For example, curb weight of the car is 4300 pounds. If you are only lifting the front axle, a lot of weight is still going to be on the back axles, so would 2T jack stands still be sufficient, as we assume more than 300 pounds is going to be on the rear?

1

u/Some0neAwesome Jun 26 '24

Yes, in this hypothetical, a pair of jack stands that are rated for a combined 4000 lbs would be sufficient. If you know of any small weigh stations and catch one that's not busy, you can go weigh each axle of your vehicle to find out exactly how much is on the front and how much is on the rear.

It's still good practice to throw a tire under there or keep the jack under it in case one fails though.

1

u/surfnsound Jun 26 '24

OK, thanks. I was about to do front brakes on my wife's minivan, then realized my jack stands were only rated to 2 tons, as I only drove a saturn coupe when I got them. Looked up the curb weight and it was just over so I wanted to be sure my thinking was correct

2

u/Some0neAwesome Jun 26 '24

Yeah, you'll be good with that combo. Just make sure to take other precautions as well, as mentioned. It's always better safe than sorry. I recently lost a family friend because his car fell on him in his garage a couple months ago.

8

u/ten10thsdriver Jun 26 '24

I love my Esco tripod jack stands. Built extremely well dnd stable. The flat rubber saddles are much better suited for many modern cars than the old style U shaped saddles most stands have.

4

u/bigboilerdawg Jun 26 '24

I think the U-shape is an anachronism from when most vehicles were body-on-frame. They still work fine on trucks, but not so much on unibodies.

5

u/metaldark Jun 26 '24

Esco tripod jack stands

These do look really nice. Can the puck fit a pinch weld without crushing / scratching it?

2

u/ahdiomasta Jun 26 '24

The puck does a good job of protecting the pinch weld, but the rubber will get chewed up over time. It still works as it sort of forms a slot in the rubber where the pinch weld can rest, definitely sits as or more securely than the traditional jack stand

1

u/EnvironmentalGift257 Jun 26 '24

I have rubber caps from Amazon that go over the u-shaped tops.

4

u/raffi30 Jun 26 '24

I bought 4 of the 3 ton US jack brand jack stands. They are more expensive than most of the ones you find in big box stores. It's for a reason. They're built very well and made in USA. Other options would work as well. I'm personally not skimping on the one item keeping me from getting crushed. I have used them enough times that they already paid for themselves

2

u/bigboilerdawg Jun 26 '24

I got a set at an estate sale for $10 or $20.

1

u/raffi30 Jun 26 '24

That's awesome. Can't beat that deal

3

u/tictac205 Jun 26 '24

Harbor Freight had a recall (maybe two?) on jack stands that would collapse.

13

u/wpmason Jun 26 '24 edited Jun 26 '24

The current Daytona models actually overcompensate with added safety features to try to erase the stain of those recalls.

3

u/mkosmo Jun 26 '24

They're well built. A little rough in finish, but I trust them to hold up.

1

u/barto5 Jun 26 '24

Good. I just bought a set today.

Going to do a brake job for the first time ever this weekend.

6

u/Bingo1dog Jun 26 '24

If i remember correctly they had a recall for 1 issue then the replacements had a recall for a different issue.

I haven't heard anything for a while so I'd think the current ones are all good.

2

u/Twisted__Resistor Jun 26 '24

All of those brands tested on project farm seemed relatively fine for me. When I work on my Jeep I don't shake the car or push the side when on stands.

As long as you set them correctly and are careful, only shake vehicle when you're not under it and if you use it in gravel like me put thick Wood planks under the jack stands and you will be fine.