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View Full Version : Can a car tow bar be used as a jacking point?


rustic
19-11-2014, 14:33
I looked on the internet, and have found nothing.
Having seen a few caravan snakes, often the caravan is on it's side and the rear of the car lifted up above the ground by it's tow bar.:doh

I have no problem with the Maverick/Terrano strength, but can you lift a car with a trolley jack located under the bar. For example a Picasso.
After all, the bar should be attached to the strongest part of the car, and often there is very little weight on the rear of most front wheel drive cars.

Looks stronger than the sill mounted jacking points.:nenau

Lazy-Ferret
19-11-2014, 14:51
I have often wondered the same thing.

Personally, I would not want to risk it on a normal car where I can't see the fixing points (as you say, on the T2, it is different, as it is right there on the end of the chassis).

They are only really designed to take a relatively small up and down force in comparison to the pulling force, but if you jacked up under the bar you are effectively putting half (give or take) the weight of the car on the towbar. The other thing is, the towbar on some cars is fixed over a long distance, often extending right up to the rear wheels, then having the over hang where the towball fixes to, making the thing act as a lever, and exaggerating the loads on the fixing points.

On my V70 though, almost every time anyone jacked it up, they used the towbar for the back, including the Volvo garage, which always made me flinch, but the tyre place up the road would always jack under the suspension, as they said it was too risky jacking anywhere else on a car.

R1cho
19-11-2014, 16:44
i jacked mine up on the towbar when putting in new springs and spacers it saved having to use a spring compressor and made the job a lot quicker, i did still use axel stands alongside the jack though as extra precaution along the chassis rails at the rear

solarman216
19-11-2014, 21:44
I would have no problem at all with lifting any car on the tow ball fixing, if it cannot take the static force of lifting the car, it will stand no chance with a dynamic one, in my book you should be able to suspnd the entire car (albeit vetically) on the tow ball, including a 2 tonne T2, Rick

rustic
19-11-2014, 22:17
I would have no problem at all with lifting any car on the tow ball fixing, if it cannot take the static force of lifting the car, it will stand no chance with a dynamic one, in my book you should be able to suspnd the entire car (albeit vetically) on the tow ball, including a 2 tonne T2, Rick

To be honest... that's what I thought.
The further you move back on a car, the less weight will be at that point, providing the structure is sound, the weight of a Picasso must be say 400 kg at the tow bar, so that's only 200 kg per side mounting, and I weigh half that...
We also load the car with more weight in the boot than that too.

As you say dynamic forces can cause damage, but a gentle lift... should be fine... depending on the car lol...

There are so many cars these days with squashed sills, where the likes of the fast fit tyre places use the so called jacking points to lift the car...:doh:doh

It would be easier to lift from one place...

solarman216
19-11-2014, 22:44
I started working life at an Austin Morris garage in Chiswick and Minis and 1100s were always lifted with trolley jack straight under the Ali sump, never any problem as far as I remember, but I was only a kid then, Rick

rustic
19-11-2014, 23:16
I started working life at an Austin Morris garage in Chiswick and Minis and 1100s were always lifted with trolley jack straight under the Ali sump, never any problem as far as I remember, but I was only a kid then, Rick

I lifted a mini once by the rear sub frame, you couldn't trust the sills... the jack kept going up, but the car didn't lift....

I looked underneath to see a mangled mass of rusted metal, the jack just cut through the remains of the sub frame...

Replacing the sub frame was fairly easy, once you had a long bolt to compress the rubber on the suspension.
Luckily, the rear mounts in the sill were sound, and didn't need welding like most did.
I thought then... if only I had the car from new and there was a rust treatment that could protect it... I could then keep it oohhh for maybe say 20 years or more..:augie
Then a few years later I found waxoyl...:clap:clap
Rustic

Thomas-the-Terrano2
20-11-2014, 00:55
agreed and atleast is an even lift, though could also lift under rear axle pumpkin.

if wanted wheels off ground would go for axle/diff as would save wasting time
only stretching suspension. then get stands in