It's not hard for car companys to build a hydraulic jack into each corner of the car and run a pump of the engine. We use hydraulics for the braking system assisted by the engine so why not to lift the car?
Saves lying down on wet tarmac trying to find out where the portable jack goes...
... yeah your right... i have just had to change my tyre, in the dark, raining and on the hard shoulder of the motorway.
2006-09-28 11:55:26 · 20 answers · asked by ? 3 in Cars & Transportation ➔ Maintenance & Repairs
You've been pretty unlucky, with modern tyre design flats are increasingly rare, which is why car co.s have moved from spare tyre -> space savers -> can of foam -> run flat tyres.
It saves weight & manufacture cost.
The problem with 4 hydraulic jacks idea, is how often would you use them, and if you left them alone for 6 years or more, when you had to use one, chances are it wouldn't work.
I've seen a bag device you attach to your exhaust and as it inflates it lifts the car, seems easier and pretty foolproof compared to a jack.
2006-09-28 12:13:12 · answer #1 · answered by strawman 4 · 1⤊ 0⤋
Cost, weight, complexity and redundancy.
Most cars will have one puncture in about 10 years.
Not enough customers will pay the extra cost (probably about £50 per corner, plus another £50 for a pump, and £10 for a control system) for something they may never use to cover the manufacturers development costs.
The extra weight will increase the fuel consumption and reduce performance for the life of the car.
As others have said, chances are that by the time the system is needed, it may not work because it has been unused for years.
Citroëns with hydropneumatic suspension used to have a system where you raised the car up on its suspension, placed a stand under the corner needed to "jack", then lowered the suspension - in the corner you put the stand, this lifted the wheel off the ground.
Cars for Touring Car racing have built in jacks to speed up pit stops, but I think these may be pneumatic, and pressurised from the same external source used to power the pit-crew's wheel "guns", reducing the complexity in the car.
2006-09-28 12:49:58 · answer #2 · answered by Neil 7 · 1⤊ 0⤋
there is no problem with a half decent jack, but too ofter cars now have no proper spare, and whats worse ordinary folk cannot undo the wheel nuts or bolts and if they can they probably cannot line the wheel bolt holes up to fit it back on.
A problem I have had is shifting alloys after they have been on for a while, I have had to use a sledge hammer on occasions.
If you get a flat, and I have had 2 in the last 10 years call the RAC, or Alcoholics Anonymous or whatever the other folk are called and you will stay safe and not ruin your R.Marney suit, or Versatchie garb, which should save you a trip to the Charity shop.
If you have a spacesaver spare 50 miles at 50 mph and room in the boot for a full size wheel ditch the spacesaver and get a proper spare, and if you aint got room for a full size spare where you goin to put the one with a flat when you take it off?
2006-09-28 14:02:30 · answer #3 · answered by "Call me Dave" 5 · 0⤊ 0⤋
would you honestly want it tho? car companys would never fit them on all there models simply because they will have to pay out more money for someone to design them efficiantly, hide them away under the car so they dont effect aero dynamics of the car for high speed driving, make them lightweight and user friendly. its just not going to happen and say you actually had these built in jacks.... how would they be operated? hydraulics? no, would take up too much room in the engine bay for a seperate fluid resivua. other than that you would have to get down on the floor and jack them up manually anyway. theres lots of ways they could be operated theoretically liek electric/hydraulic etc etc but there to impractical, electric would require seperate batterys and or extra wiring, then there would have to be somewhere for a controller of some soret, its just not going to happen, i agree with the thought of spending £30 or $60 on a little trolley jack is a simpler resolution
2006-09-28 13:16:15 · answer #4 · answered by Escort_Turbo 2 · 0⤊ 0⤋
The Ford Pilot circa 1950 had inbuilt hydraulic jacks that were operated by fitting a lever onto a pump under the bonnet. A selector switch determined which of the four rams would descend. I believe that some London taxis had a similar arrangement.
2006-09-28 12:22:33 · answer #5 · answered by Clive 6 · 0⤊ 0⤋
Safety - Safety - Safety is the issue. It's unfortunate you have to change a tire in the Dark but hey the odds of you trying to set up your Jack on uneven Ground are even greater. And who's going to come running when the Jack gives way ????
2006-09-28 12:03:02 · answer #6 · answered by rwrocketrider 2 · 0⤊ 0⤋
Cost is too high. Adds weight to car. Requires maintenance. Flat tires are a rare occasion .
You can buy a small wheeled hydraulic jack for your trunk.
2006-09-28 11:59:24 · answer #7 · answered by R1volta 6 · 0⤊ 0⤋
They did in the 50s Wolsley Riley MG all used a hydraulic system tht enabled you to change a wheel.
2006-09-28 12:08:36 · answer #8 · answered by mick 6 · 0⤊ 0⤋
One car company experimented with this idea many years ago but found that the cost was too high and would increase the price of the car by about £3000 at todays value to put it into production.
2006-09-28 12:45:45 · answer #9 · answered by Anonymous · 0⤊ 0⤋
Because it would take up space.
Then if you do have 4 jacks on al sides of the car, the car designer will have to account for it. Dont forget the safety specs of the jacks now being part of the crash test.
To much responciblity would be passed to the designer of the cars.
2006-09-28 11:59:20 · answer #10 · answered by Anonymous · 1⤊ 0⤋