Using four jackstands

[mjoekingz28]

I read somewhere (maybe the jackstands manual) not to lift both ends of the vehicle at one time. Well, I have shunned that warning a time or two to rotate tires or whatever. Well, I am wondering is there any merit to this caution.


I bring this up because I had read some place to have tires mounted before inflating them. I ignored this warning as well because I thought nothing of it, or was lazy, etc. w/e. but I have since seen videos of tires popping and becoming more dangerous than safety glasses can protect.


What say you?

 

[RamFan]

I don't see a single problem with 4 jack stands.

 

[eljefino]

The issue as I see it is that the jack lifts in an arc, eg not directly straight up. A wheel jack pulls its own wheels under the car, provided the concrete surface is smooth and its top catches a good lip, like a pinch weld.

With the opposite side/ corner of the car on tires, this works pretty well. With the other side on jack stands, sometimes the jack stands like to do a "wheelie".

I've put cars on 4 stands for complicated work, it's more trouble than putting one end on 2 stands times two. Generally I put the rear axle up (on pinch welds just forward of the rear wheel arch) then when I go to lift one front corner, the whole front end lifts up! There's no suspension sag in the rear anymore to "take that in".

This is easy if you have a K-frame crossmember with a center jacking spot, but creepy when you use a corner and the torsional strength of your chassis lets you lift.

Having surprised myself by having probably 80% of the car's weight on my jack head, I scramble to get stands under both sides. The unjacked front corner might be a half inch lower, due to chassis flex.

Which brings up the point, how do you know you have good weight on all four stands, keeping them stable?

 

[3311]

I don't like to use 4 jackstand unless absolutely necessary.

 

[Brad_C]

Originally Posted By: eljefino
Which brings up the point, how do you know you have good weight on all four stands, keeping them stable?


I run at the car from all 4 sides and hit it as hard as I can. If it rocks at all it's not right and I'll re-set the stands. When I get them all set right it does not move at all.

I often put the car up on all 4 when I do engine or drivetrain work. I use the factory jacking points, but then I put *another* 4 stands with screw adjusters. 2 under the rear axle and 2 under the front suspension control arm pivots. I get paranoid because I use all stands at maximum extension so I can get 500mm clear under the car, but I push and shove it as hard as I can to check everything is as solid as I can get it before I go under.

 

[Vikas]

Originally Posted By: 3311
I don't like to use 4 jackstand unless absolutely necessary.
Why? It seems to be the best way to jack up all four wheels.

 

[JHZR2]

I'm always worried about this though people do it. I've always figured if I were to do it, I'd run two jacks to at least balance it a bit. But I've never had the need to do so.

 

[gathermewool]

The logic behind not wanting all four corners up is one of stability. Brad_C's method for verifying stability sounds silly, but it's pretty much the only way to know you've got a stable platform. Otherwise, if you get one jackstand to shift, move or fall out due to lack of pressure and friction against the ground or car, you could get the other three to also lose stability and then the whole thing literally comes crashing down.

With two stands set, the other half of the car is held by chocked tires (ideally they're chocked, but a set, working parking brake will do in a pinch, so long as you're not banging around from beneath the car.) The tires will have a lot more friction against the ground (again, especially if they're set and chocked) and the suspension will distribute the load so that it is less likely to teeter.

With access to a lift at the hobby shop I've never had to jack all four sides, but I'm not sure whether I would for more than just a tire rotation.

 

[SHOZ]

When rotating tires I jack up from the side and use one jack stand near where the jack is.

Today I'm bleeding my clutch and the rear has to be higher than the front to do it properly without a level lift. So i have the back jacked up high and on two stands.

When I changed out my clutch I used 4 stands.

 

[Vikas]

Originally Posted By: SHOZ
When rotating tires I jack up from the side and use one jack stand near where the jack is.
Next time, can you take some pictures? I could never see how both jack and jack stand can fit on the side pinch weld.

 

[SHOZ]

Originally Posted By: Vikas
Originally Posted By: SHOZ
When rotating tires I jack up from the side and use one jack stand near where the jack is.
Next time, can you take some pictures? I could never see how both jack and jack stand can fit on the side pinch weld.


I never use the pinch weld. I use the under body rails with a block of wood.

 

[Vikas]

Do unibody cars have that under body rail?

 

[SHOZ]

All the ones I have had do. They are made to allow the drivetrain to slide under the car in a head on.

 

[threeputtpar]

Over the weekend, a local guy replaced the torque converter on my Audi for me. He did this with the car up on 4 jack stands, with the front being higher than the rear. It looked like the car was in takeoff position.

He and the car are still alive to talk about it. It sure did help that he had a really nice long reach, low profile floor jack to get under the car properly.

 

[stephen9666]

Originally Posted By: mjoekingz28
I read somewhere (maybe the jackstands manual) not to lift both ends of the vehicle at one time. Well, I have shunned that warning a time or two to rotate tires or whatever. Well, I am wondering is there any merit to this caution.


Interesting. I've never before heard this claim. Can you provide a link to a document explaining it?

I can see the issue mentioned about the jack not being able to roll, but that shouldn't be an issue on concretes less it gets hung up on a big crack or something.

I've had a car in four jack stands many times and I'll continue to do it. I'm very safety conscious, but if you do it safely I see no reason to worry about it.

 

[surfstar]

Originally Posted By: mjoekingz28

I bring this up because I had read some place to have tires mounted before inflating them.

What say you?


I say "what?"

 

[mjoekingz28]

Originally Posted By: stephen9666
Originally Posted By: mjoekingz28
I read somewhere (maybe the jackstands manual) not to lift both ends of the vehicle at one time. Well, I have shunned that warning a time or two to rotate tires or whatever. Well, I am wondering is there any merit to this caution.


Interesting. I've never before heard this claim. Can you provide a link to a document explaining it?

I can see the issue mentioned about the jack not being able to roll, but that shouldn't be an issue on concretes less it gets hung up on a big crack or something.

I've had a car in four jack stands many times and I'll continue to do it. I'm very safety conscious, but if you do it safely I see no reason to worry about it.



Yes, friend, sometimes we can not or should not trust our judgement taking on new ventures. You know there is always that one unforeseen circumstance!


As you request:

I wish I could give you a link, but I cannot see how on the iPad-there are many functions I have lost going from a desktop to this. Alot of typos too!

Just do this....type ......craftsman jackstand manual....... Into Google...it should be the first item


C.shld.net

On page 3 in the orange warning section you should find your text.

 

[spasm3]

I've done it. I can't remember what for. But i kept a tire on each side under the frame rail just in case. Before getting under it, i shake and try to see if i can shake it off the jack stands.
P.S.
Actually , i had my travel trailer on the jack stands when i took the wheels in for new tires. I did get under it and repainted the frame and axle.

 

[Merkava_4]

Originally Posted By: mjoekingz28
I read somewhere (maybe the jackstands manual) not to lift both ends of the vehicle at one time.


You don't have any choice in the matter sometimes such as dropping a transmission out the bottom.
That car has to be very high up in the air and the only way to do that is to get it up on all fours.

 

[B20z]

Originally Posted By: threeputtpar
Over the weekend, a local guy replaced the torque converter on my Audi for me. He did this with the car up on 4 jack stands, with the front being higher than the rear. It looked like the car was in takeoff position.

He and the car are still alive to talk about it. It sure did help that he had a really nice long reach, low profile floor jack to get under the car properly.


I'm glad it worked out for him, this time. I'd never go under a car like that. I use 4 jack stands occasionally but only for tire/brake/hub work. Wish I had space for a lift.

My thing with pushing or rocking the car to check your stands is that if the car falls during your "test" how's that going to help you? Now your brake rotor has hit the ground or your jack stand has spiked something attached to the underbody. I mean sure, you saved yourself from being crushed but you're going to wish you had been.