Best Car Jack Ever

[The_Blur]

You're on a trip for business, and your wife gets a flat. The last time this happened, you were by her side and could help. All you had to do was jack up the car for her and change the tire. In all honesty, she could change the tire, but the jack was hard to line up, and pumping it wasn't really easy for her. After all of your hard weight training—some might call it carrying the groceries for her or helping her with her bags at the mall—you're in much better shape to do this work. With you out of town, and she's stranded. :(

It's a good thing that you put a special car jack in her car. Now, she can get that tire replaced with a lot less effort. Aren't you a hero?

[2ndgenz28]

how much exhaust back pressure/psi can u safley put on a engine???

Then how many to raise a SUV??

[TheCaptain]

That could be helpful. Till some idiot flips their car over and tries to blame the manufacturer!

[DGthe3]

Originally Posted by 2ndgenz28

how much exhaust back pressure/psi can u safley put on a engine???

Then how many to raise a SUV??

You don't need that much pressure for this. I'd guess that the air bag (exhaust bag?) has a contact area of 3, maybe 4 square feet. And it only has to hold about half the weight of the vehicle. So, 3.5 square feet = 500 square inches. For a 5000 lb SUV, it would have to lift about 2500 lbs. So thats only 5 pounds per square inch of pressure. Turbo chargers add several times that without much issue. But, if you're worried ... upgrade the exhaust system first with something thats a bit less restrictive. That would more or less counter the added back pressure of the bag.

[8cd03gro]

Originally Posted by DGthe3

You don't need that much pressure for this. I'd guess that the air bag (exhaust bag?) has a contact area of 3, maybe 4 square feet. And it only has to hold about half the weight of the vehicle. So, 3.5 square feet = 500 square inches. For a 5000 lb SUV, it would have to lift about 2500 lbs. So thats only 5 pounds per square inch of pressure. Turbo chargers add several times that without much issue. But, if you're worried ... upgrade the exhaust system first with something thats a bit less restrictive. That would more or less counter the added back pressure of the bag.

The top surface area is probably more around 6+ ft^2 if the entire top surface were to be touching the car directly, which it wouldn't but still. It looks like the cylinder is at least around 2 ft across which would leave a 6.28X ft^2 of area on the top surface assuming the "bubble" is cylindrical, which it looks like it is. That could just be the pic though. Also, the force vector of gravity is always downward, so you're holding considerably less than half the total weight once the car is at an angle like it is once the bag is fully inflated. The physics of it makes it a great invention, but for practical use I don't know if I would trust it for anything other than a tire change. I sure as hell would not be under that car with that thing holding it up. I guess if it did burst on you, at least you'd get a nice big wiff of CO to calm you down while you get crushed

[GJG]

be really nice if i actually had a spare tire......she's still gonna call me even if she's 3 states over

[christianmotox]

Thats pretty sweet, i had one back when i had my FJ, about 2 or 3 years ago. Never got a flat.

so i never used it.

[Xanthos]

Originally Posted by 8cd03gro

The top surface area is probably more around 6+ ft^2 if the entire top surface were to be touching the car directly, which it wouldn't but still. It looks like the cylinder is at least around 2 ft across which would leave a 6.28X ft^2 of area on the top surface assuming the "bubble" is cylindrical, which it looks like it is. That could just be the pic though. Also, the force vector of gravity is always downward, so you're holding considerably less than half the total weight once the car is at an angle like it is once the bag is fully inflated. The physics of it makes it a great invention, but for practical use I don't know if I would trust it for anything other than a tire change. I sure as hell would not be under that car with that thing holding it up. I guess if it did burst on you, at least you'd get a nice big wiff of CO to calm you down while you get crushed

Oh, you definitely wouldn't want to be under the car with that being the sole lift. But, it'd get the car up long enough to get a jack stand underneath.
- X

[2ndgenz28]

Would it pass a shake test???

[2ndgenz28]

only half on the bag, so its wanting to squish out, a big gust by a passing semi could f you up mid tire change.

[Xanthos]

My brother and I once stopped to help a lady change a tire on the side of the interstate. She said she had no idea how to change a tire. We asked if she had a jack, and she said "yeah... I think I have one in the trunk..."

And proceeds to pull out a 2.5 ton floor jack. We were both like "WTF?"

She said her brother-in-law bought it for her for her birthday, because she got flat tires a lot.
- X

[BigDan]

Yeah these have been out for years now and Northern Tool sells them. I'm thinking about getting one after reading all the poor reviews on the Chinese built Craftsman and most other brand affordable aluminum floor jacks.

$119 right now at Northern Tool
http://www.northerntool.com/shop/too...&ci_sku=144747

On the way to the local track last time I went I was going to go buy Harbor Freights 3k Rapid pump aluminum floor jack which is getting good reviews but I said fug it and drove 120 miles on my DR's

Harbor Freight Rapid Pump
http://www.harborfreight.com/rapid-p...ver-47246.html

[2ndgenz28]

Course I should not judge to much, how many here every used the old GM bumper jack with the slot in the bumper, always fun the way they rocked as it went up, let alone hoping the rusty bumper is gonna hold. Way before anyone but a shop had a hyrdo, if you had to jack it up high from the suspension hanging, its was scary.

[Revo1]

Here he is