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Dangerous car jacks?

So, a few days ago I was ready to replace an O2 sensor on my Dodge Durango, lifted the car, placed a couple of jacks under the frame and crawled under the car.

It wasn’t ten seconds when suddenly I had this overwhelming feeling that I shouldn’t be doing this. I have done this hundreds of times and never really had any second thoughts crawling under a car and working on the underside, but this time it was different. Anyways, I removed everything, let the car down and went inside to have a cup of coffee and had a good day doing something else.

The jacks I used are rated at 2 tons. This car weights about 6700 lbs. Seems that I have been playing with an accident to happen. I plan on using my son’s scissor lift which is rated at 8000 lbs. and I have more space to work. But I purchased a new pair of 3-ton jacks to be used in the future on my other cars, which are not as heavy.

I compared the new jacks with my 2-ton jacks, and I noticed something that I found very disturbing on the 2-ton jacks (the ones I have been using for over 15 years).

The locking pawl slides over the locking handle and is held in place by only a skinny pin. The locking pawl is the part that holds the ratchet bar in place. There is no other safety pin or bold to backup this mechanism. The complete weight of whatever part of the car rests on the ratchet bar and its weight is subsequently held in place by that skinny pin. In other words, in the past I had half of the cars weight rest on two skinny pins, one in each jack. Thinking back, it sounds like attempted suicide to use these types of jacks on cars.

The new 3-ton jacks (the red ones) have the same mechanism but have a heavy-duty double lock.

having the secondary locking bar is definitely better than relying on the single locking mechanism

still, that pins you are so concerned about are not critical for safety, as the entire pawl is self-locked once the weight is applied from the top

having 3 ton vehicle, it’s definitely a good call for the 3-ton rated jacks

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I know others disagree but I really don’t like jack stands. I much prefer ramps. You have to listen to your intuition sometimes. The jacks stands though that I use, have the pin going directly through the bar so the whole pin would need to shear for them to come down. I’m not familiar with the type you have but I consider those ratchet types dangerous.

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I am afraid to use my 20 year old wheel ramps, A little rust, I think I should throw them on the parkway for the scrappers. I used them a couple of years ago, they were fine, but I am not crawling under cars much these days.

If I’m working under a vehicle at home I rest the tires on old rims. So far it has been a bullet proof method. If I’m removing the wheels I leave the jack supporting the vehicle and stack old rims on the rims I took off for a back stop. Again bullet proof

.When I see cars on scissor jacks while being worked on I cringe unless the wheel is under the frame

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When I started reading your post, it scared the heck out of me. What you are calling jacks are jack stands.

Your post made it sound like you were under the vehicle supported only by two hydraulic jacks.

As far as your Durango, more than half of that 6700 is on the front wheels. That is getting very close to the rated capacity of the 2 ton stands, I like to have plenty of reserve capacity.

I threw out my old steel ramps years ago, they creaked and groaned. I now use plastic honeycomb
Rhino Ramps, much safer. When I use the stands I always back them up with something.

I’m the wrong side of 80 but I still enjoy working on a car.I just try to make sure I have everything I might need in reach before I start because getting from standing to under the car and back up is frequently the hardest part of the job.

When I do my once yearly oil change now, I do it when the engine is hot. I pull the car up on the ramps and pull the drain plug, remove the filter housing, change the cartridge and let the oil drain overnight.

Although my Camry has a claimed capacity of 4.7 quarts, it take 5 qts to fill it when I do that. I wish Toyota used cross hatching on the dip stick, the oil stays so clean it is hard to read on my 8+ year old car even after 6 months.

I was thinking of getting a new one, but after reading the problems with direct injection engines I think I will just keep driving this one. so far the only thing other than wear items and oil changes, the only thing I have done is replace a w.washer pump. I watched a youtube video first to see if there were any surprises and the idiots who made it wanted me to replace the bumper cover,ridiculous!

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I do not trust ramps at all. For changing the engine oil and filter, transmission fluid and filter, fuel filter mounted under the vehicle, replacing O2 sensors, etc, nothing beats jacking up the front one wheel at a time, and putting a wheel (from a different vehicle) laying flat under each front tire. You can safely do this even on a dirt or gravel surface.

For doing work which requires that the wheels come off, such as brake or suspension work, the only option is to use jack stands. Jack stands require a flat paved surface, and cannot safely be used on a dirt/gravel surface.

That is with 7 occupants and cargo, the curb weight of a first generation Durango is 4200 to 4500 lbs.

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Plus, if you’re only using two, you’re not supporting the whole weight of the car. The wheels on the other end are supporting part of the weight. You’d have to do some weight and balance calculations to figure out exactly how much weight the stands are actually supporting, but almost guaranteed you weren’t over the weight limit of your jack stands.

That said, it’s a good practice to build in a margin of safety - if your stands are rated for 2 tons, make sure they never support more than 3500 pounds, for instance.

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Yea you had me confused for a moment… jacks are not jack stands.

Most of the other things i was going to mention @oldtimer_11 and @thegreendrag0n and @Rod_Knox covered fairly well.

That pin that freaked you out is only responsible for moving the locking pawl in and out of place… no more no less

Once in place the downward force of the vehicle locks them firmly into place and they do not rely on that roll pin in any way shape or form and honestly those jack stands are more than adequate… the only thing u need to watch is where n how u place them. You were quite safe if u placed them correctly

The two stands probably had to deal with less than half of your vehicles weight…divide that by two and each stand was basically yawning waiting for things to get “heavy”

Its never a good idea to argue about a persons feelings when they are the ones crawling under the lifted metal object at hand… so i usually just trust the persons gut feeling. Always trust your instincts… but from the comfort of where i am… with the evidence provided, i don’t see anything you should’ve been freaked out about.

Been watching any cheezy horror movies lately? Anyway… stay safe

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Is that over or under? :rofl:

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I concur with the others. The trucks weight is not carrried by those roll pins. The latching pawl is supported by that big thick latch handle in double shear. I have been using stands like that for decades. Stands… plural. My Mustang is currently sitting on 4. I give it a good shove to make sure it isn’t wobbly before getting under.

I own 10 of these 2 ton stands. My truck weighs 5600 empty and I like extras!

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I think this lesson I learned 46 years ago is an Everytime requirement. But it’s probably one of the most overlooked steps taken. If There’s two things I take seriously in safety reverance, it’s gun handling and proper lifting of vehicles. If I ever found my son working on a vehicle with Jack’s only I think I would pull him out and administer some kind of hand language. I’ve never had that problem though, because he has witnessed me with jackstand safety all his life. He may not practice as safely as I now do but even now he never gets under a vehicle without it being secured properly.

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Thanks all. Feeling a little better now. Maybe just a moment of paranoia. Now back under the car to change that sensor.

Nothing wrong with a little caution in the realm of self preservation i always say.

If you really want to ramp up the fear factor I could tell you some personal stories of vehicles that were hell bent to get back on the ground despite me being under them… but I don’t think they would be helpful here at this juncture.

Paranoia is not your friend…

A couple years ago my neighbor had the front of his kids car hoisted on a jack and he was under the thing, banging away at something. It made me so nervous I brought my jack stands over for him to use. I didn’t want to tell him how to do anything but i didn’t want to try and pull him out of there either if the jack came down.

Still I don’t like either jacks or stands. I was under a car once when my BIL was hoisting an engine in and the chain slipped and down it came. I’m thin so no harm done but I added it to the list of places I don’t like to be.

Personally, I don’t fully trust any jack, jackstand, car ramp, or even a lift in a shop. The "what if’ factor is always present.

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I generally agree with you about not setting jack stands on gravel. However, I do it all the time in my driveway with no worry. A few years ago I had a new concrete back porch poured. When the contractor finished the porch he asked me if he could dump his leftover gravel on my gravel driveway. My driveway was needing new gravel anyway and I recognized the gravel he had. It was medium-size gravel with fine dust mixed in, sometimes used for roadbed base. Since that gravel was added and packed down, my driveway is hard as concrete. I have set my car or truck on jack stands many times, even when raining and those jack stands are solid and never sink into the gravel. I have a F150 sitting on jack stands on that gravel for several months now and no problem. But, you are right. I wouldn’t do that on a normal gravel driveway.

I have always been a little nervous about crawling under a car on jack stands. I have had my '92 F150 sitting on jack stands for several months. It needs new brake lines. At first I just used the two 6T jack stands I had. Then, I decided to use better jack stands and bought a pair of 6T jack stands with the safety pin similar to the red ones in your picture. So, now I have the rear axle sitting on 4 jack stands and it hasn’t fallen yet. Now got to get to the brake line.

Ah…NO. You only put one corner of the car on the jack stand. With 60% of the weight on average is in the front of the car(on front engine vehicles), then at most you’re putting 2010 lbs on that one jack stand that is rated for 2 tons.

Ramps are great for doing oil changes or anything where you don’t have to remove a wheel. Want to replace the front brakes, then ramps won’t work. I do however do NOT like any car ramp you can buy at any parts store. They are junk…So I built my own. Basically a stack of 5 2x10 of different lengths and an angle cut at the end. Started with a 6’ length that sits on the floor. Then a 5.5’ length on top…and the final length is about 4’. Extremely durable…and each ramp weighs about 50lbs. Something like the pic in the link here