Recent post regarding a Ford Focus with wheel bearing problems set me thinking.
At the launch of a new car we are told of the tremendous testing procedures involved before they are launched on to the public.
Driven in the Sahara desert at tremendous temperatures and then in the frozen wastes of Siberia.
Every part tested to destruction far beyond any road user could emulate.
And then we hear of manufacturers recalls on new models with such items as wheel bearings, brake disks, handbrake cables etc etc which have built in design faults.
And yet a component such as a wheel bearing which had been perfected decades ago to the extent that on some models they simply never failed during the life of the vehicle. So I think why.. do they change the basic design and incur the huge costs of having to put this right at a later stage.
And why.. dosn't these faults reveal themselves during the epic testing routines they supposedly put them through.
alvin
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IMHO engineers are too clever nowdays.
In the old days you took an off-the shelf bearing which you knew was more than adequate.
Modern engineers design a bearing down to the minumum weight whose strength is predicted to be adequate by their computer.
I would prefer something on which my life depends to be over-engineered, the cost must be measured in pence per component.
However, it reminds me of a story of a Ford employee who got a bonus for saving the company tuppence per gearbox by eliminating a drilling.
This was approved by the design team.
Only when warranty claims started to come in did they re-check and discover that the "surplus" drilling was an oilway.
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I can remember the advert a couple of years ago of a Vauxhall Corsa which
was driving through a ravine where there were flaming rocks and molten lava
falling around it. There were huge metal spikes coming out the ground and it
looked like the world was going to end. Well, it gave the impression that no
matter what was happening outside you would be safe and secure in a Corsa.
Do you remember that? It was just when Vauxhall were getting a load of bad
publicity because although the car could stand up against armagedon it just
couldn't fight off the effects of a little bit of birdsh*t. Advertising?
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Reminds me of an old line from Flanders and Swann when MOT 10-year testing was introduced, along the lines of "they're testing cars over 10 years old now and there's talk of bringing it down to 7 and even 5 years. Who knows, they may eventually get to checking them before they leave the factory!"
:-)
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Ah yes, the 10 year test!
I remember the brakes were tested by taking the car out and stopping with an accelerator thingy on the floor. I was allowed to go along. Now, the chap clearly thought such an old heap would struggle to pass, whereas I had been out fine tuning the brakes with all the adjustments you had on a vintage Lagonda; result, big boot hard down, all four wheels stop, upset residents rush to windows to see what made the noise and smoke. Shaken but unbowed, he then found out you could get the same result at the rear with the hand brake (separate shoes in double width drums)! Not a bad bloke, though, he quite soon had some idea of working the Z box with clutch stop.
Fortunately I was shot of the Austin 8, which with similar treatment would have turned sharply either to the right or the left with no great decelerative effect. That was a vehicle which conditioned you to putting foot down hard at all possible times and not losing speed through corners, to get anywhere at all before nex
I do not think, except for the clueless who were with us even then, we were unsafe in such things; we just allowed for their foibles.
Those were the real motoring days, I just wished I had some money (how I hated contemporaries who had, and wasted it on a Zodiac when they could have a TR2, or a Mark II when they could have an XK).
Oh well, there was BSA, with Amal RN amongst other things.
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Engineering is a compromise: it would be easy to design a car that will, with correct and minimal maintenance, last a 'lifetime'. However, lasting a lifetime isn't the only requirement for a modern car: it must be efficient and have performance; it must be safe and attractive; it must carry 2,4,5,6,7 people and be manouverable.
In essence, over-engineering components will not only add additional material and tooling costs, it will also add weight which in turn will contribute to poor performance both in terms of acceleration and fuel economy.
The skill of the engineer is to optimise these requirements. If there were one solution there would be one car. . .
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Why should Ford/GM/Nissan/Toyota design you a car that will last for 20 years with minimal refurbishment required when they can sell you car with a life expectancy of 7 years? And new is always better than old, obviously. The answer? Bangernomics/Landrover/Kitcar.
AP
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All engineers are mechanically sympathetic;no matter how severe a test they come up with-a little old lady will still break a car as she drives out of the showroom and, if you believe the one about Ford deleting a drilling on the gearbox,you don't deserve to own a car.
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Re car quality:
perhaps as you drive slowly away from the dealership with your new car it might be the time to recall the thought going through the astronaut's mind as the great machine shudders beneath him and slowly starts to rise: "all the parts beneath me were supplied by the lowest bidder".
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I think you put all this into 2 catagories.
1) Design faults.
2) Manufacture faults.
The A-class and Audi TT spring to mind when thinking about design faults. As for manufacturing faults i would agree the culture of 'only the cheapest will do' plays a major part in this.I spent 4 years in a precision engineering company as a quality inspector/tester. You soon learn that no matter how hard you try to eliminate faults you can never completely get rid of them.
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Had a look under a Vauxhall / Renault Van today. A Movano or something.
The rear road springs - single leaf, are made out of some sort of plastic. A torch beam shines through them.
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j.cronin
I did describe the Ford gearbox drilling saga as a story.
Regards
B
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Alvin
My father worked for many years at Ford, and I used to read the in-house magazines. Your comment about wheel bearings reminded me of one problem which would not be sorted by road testing.
Early Fiestas were built in Spain (Valencia), and the UK bound vehicles were moved by train. There was a spate of wheel bearing failures, which took a while to diagnose. It seemed that the problem was the long rail journey. The vehicles were stationary, and so the bearings were subject to repeated impact loading in one position. A small number of vehicles suffered damage to the races - pitting where the ball bearings were impacting. The cure was to change the grease spec for the bearings. No amount of road testing would have found that one!
Regards
John
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Composite (i.e. glassfibre) leaf springs on vans are old hat. Sherpas had them 10 years ago - I think they were the first van to do so. The springs were developed by GKN, and I haven't seen any Sherpas stranded at the roadside with broken leaf springs. I'd be more worried about all the plastic components under the bonnet - we now have plastic manifolds, throttle bodies, cam covers, and it's only a matter of time before someone comes up with a plastic cylinder head. (Former Triumph TR7 owners will point out that their cars had a chocolate cylinder head....)
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