Wednesday, 20 August 2014

I'm ditching my hi-lift for a better idea

Hi-lift jack versus air-jack.

During shooting of 4WD-season-4 I visited my old pal John Rich at Stoney Ridge to drive the new Isuzu and to get it stuck. This was successful, although I have to admit, the Isuzu put up a struggle. In John’s riverbed, finally we managed to bog it down to the belly. The plan was to demonstrate the use of an air-jack. Takla makes the best one I’ve seen, and they asked me to “Give it a meaningful test”. So I decided that I should give it the ultimate test – to see if it could, practically speaking, replace the Hi-lift jack.

 Why replace the hi-lift?
The hi-lift can be a nasty thing. It’s heavy. Weight is one thing that all overlanders have to (or should) worry about. So often the hi-lift is attached to the vehicle in inappropriate places: the roof rack is high up and bad for C of G. On the bull-bar is extremely dangerous. On the tailgate standing up is probably the best. Another alternative is to dismantle it and have the mechanism in the vehicle with just the shaft on the roof-rack. This is probably the best, as the mechanism doesn’t get dirty and much of the weight is lower down.
In use it’s dangerous, and even experienced users handle it with great respect. It can kick up, and smash teeth and faces. It can jamb at the most inopportune moment, only then to kick up. Once up, the vehicle is extremely unstable. A single person using it to get a vehicle free must be oh so very careful that the vehicle doesn’t fall at the wrong moment. However, it can get a vehicle out of a very gooey mess, very effectively and is a lifesaver. When nothing else works, call on the hi-lift. It is just the job.
So the question is, can an air-jack be called upon in equally difficult situations? This was my quest, to see if it could.
On the surface, and air jack does not need a jacking plate and even in the softest ground does not sink in at all. So I don’t need to carry a heavy and bulky jacking plate. It can drop to approximately the height of a hi-lift, albeit with a larger surface area. So more preparation is required of the ground with an air-jack. But, add a jacking plate, and the two are about equal.
The Isuzu had sunk up to its belly, so there was a vacuum formed underneath. In this situation, a winch would have to work very hard indeed, where a lift would be required. It seemed an adequate test. John has been using an air jack in preference to a hi-lift for years, and he is one of the few people I know who recovers a vehicle almost on a daily basis, running advance recovery courses as he does. And he ditched his hi-lift some time ago.
The recovery was not only a success but proved to me that an air-jack is like a hi-lift in that it needs knowhow and experience to get the most out of it. But it is safer (can’t kick anyone and has a safety valve), more stable, is as easy to make fine adjustments (the Takla version is, with its valve system) and better at lifting a vehicle. Yes, better.
It’s better because one does not need to make any modifications to the vehicle to use an air-jack on the front, sides or back. With a hi-lift, the vehicle has to be modified with bumpers or rock-sliders, both very heavy items. It needs far less physical effort to use. And it can easily and more safely be used by a single operator.
On the downside
An air-jack cannot be used as an emergency winch. But, actually, neither can a hi-lift. It can in theory, but not in practice. It requires rope with zero stretch to winch a vehicle at about twenty-feet-per-day. The procedure is painfully slow, in short steps, almost all of which is used to take up slack and stretch. And who carries that much plasma rope in their kit, who doesn’t already have a winch?
The air-jack is easier to stow, and can be strapped to a spare wheel on the rack on the back. It’s lighter and is not prone to sticking. It can be damaged by rolling over onto a spike, but the good ones come with a repair kit.
All in all, looking at this closely and with the experience at John’s, I have concluded that there is only one significant (if you can call it that) advantage the hi-lift has over the air jack, and that is that it doesn’t look as macho. And I propose that it is for this reason why most overlanders will not swap their hi-lifts for this ugly, oversized air-spring.