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Wheel alignment at Micheldever Tyres certainly seems to have reduced the wear rate of the front tyres on my Peugeot 405. I had had the tracking done elsewhere but still suffered from excessive wear of the outside shoulders of the tyres. The improvement may, however, be due to requesting that they set the tracking parallel rather than the toe-in as specifed by Peugeot. The tracking was worth the £15-£16 it added to the tyre bill & has paid back alredy in extended tyre life.
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On the average car, pinpoint accuracy isn't neccessary or possible. I don't know of a manufacturer who quotes 'exact ' figures for toe, camber, castor or kpi. No matter how accurate the measuring gear is, readings can't be any more accurate than the inherently 'floppy' steering gear - to which it is attached -allows.
I still use a 30yr old 'Optical alignment gauge', this uses old fashioned light rays and mirrors. My, how things have changed !
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I still use a 30yr old 'Optical alignment gauge', this uses old fashioned light rays and mirrors. My, how things have changed !
But HAVE things changed? With reference to an earlier thread, I'm still waiting for someone to explain how taking readings electronically gives a better result than reading them off a scale.
Either the wheel alignment is within tolerance or it isn't and, in my experience, perfectly acceptable results can be obtained using optical gauges.
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I agree that optical gauges, properly used, are just as good as electronic. Any figure quoted by a manufacturer for alignment, castor etc. will have a range of tolerance. This is necessary to allow for the manufacturing tolerances in all the various components, plus the inevitable wear after the vehicle has a few miles under its belt. It is well worth checking these things on a new vehicle after a while as rubber bushes etc. will settle with use. With the trend for wider and wider tyres, even when properly adjusted you are going to get more wear on the edges which could look like bad alignment, especially if you drive enthusiastically.
On the a similar topic, I remember reading some years ago that when taking a vehicle for an alignment check it was a good idea to stop the vehicle using the handbrake when putting it on the ramp as the footbrake makes the front of the vehicle move down slightly and thus slightly altering the geometry. (Assuming a rear wheel operating hand brake). Is this an old wive's tale?
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Just thought I'd give a couple of examples of failed electronic tracking ...
Case 1.
I bought a 29,000 mile 1980 Vauxhall Royale Coupe in 1986. Shortly afterwards a Peterborough garage offered free wheel alignment checks using their new and 'highly sophisticated' electronic tracking equipment. I thought I might as well take advantage of this offer.
The 'technician' (the owner of the garage) reported that the tracking was way out - "right off the scale" - and asked if I wanted it reset. I was amazed at this because the treads were wearing perfectly well with no sign at all of feathering. I declined a reset, saying that I would check over the steering and suspension components first.
Back home, I found everything to be fine on the steering and suspension front so I borrowed the local garage's Dunlop optical tracking equipment. I drove the car onto a flat and smooth area of concrete and rolled it backwards and forwards a couple of times to 'zero' the suspension. I then zeroed the two main parts of the optical equipment by placing them face-to-face and checking in the viewfinder that the pointer was in the dead centre of the scale.
I next placed the equipment against the rims of the two front wheels and checked the pointer position and this showed the tracking to be spot on (i.e. it showed the specified toe-in figure). I then moved the car so that the wheels went through a 1/4 turn and carried out the check again, to confirm that there was no buckling of the wheels. The tracking was again spot on. I didn't do a four-wheel tracking check, though the equipment includes the bits to do this if required.
Over the following three or four years I got many thousands of miles more out of the tyres without any adjustment of the tracking and the wear was so even that the wheels/tyres would stand up on their own off the car.
Case 2.
When I bought my BMW in May 2000, it had just had a new steering part fitted but there was no sign that the tracking had been reset. I mistakenly decided that I should have the tracking, and the (non-adjustable) caster/camber angles, checked electronically with the all-singing equipment operated by another Peterborough tyre company.
From a distance, I watched the readings on the screen as the fitter struggled to reset the tracking. Red (out of tolerance) figures kept appearing for one side of the car then the other and he failed altogether to get the necessary all-green figures. I was then told by the depot manager that "Everything is as it should be. Nothing needed setting so we don't need a print-out and there'll be no charge".
To cap it all, they had managed to move my steering wheel from 10-to-2 to 11-to-3 and when I complained of this a couple of days later, they said that they would correct it but would have to charge me a fiver because "anything could have happened since you took the car away"!! I corrected it myself of course.
I was later told that the 'wheel alignment technicians' at that tyre depot are part-timers and include a builder's labourer who does it to earn some spare-time cash!
Conclusion.
Perhaps Micheldever do a very good job *because they know what they are doing* and this is very much more important than the type of equipment that is used.
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I would be interested to know how a 4 wheel alignment could be carried out using optical equipment. I'm fairly sure that measurements are required between sensors to establish the centreline of the car and hence the thrustline of the wheels.
I went to a chain in London for wheel alignment and was told the printer was broken and a printout was not available. Turns out they hadnt adjusted it correctly.
I wonder if the machine will only print out the final set of readings, therefore if they do it wrong (or cant do it) they won't want to give a printout.
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I would be interested to know how a 4 wheel alignment could be carried out using optical equipment. I'm fairly sure that measurements are required between sensors to establish the centreline of the car and hence the thrustline of the wheels.
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Keith, I haven't used the 4-wheel part of the optical apparatus but I think it only checks the rear wheel toe in/out and checks the relationship of the rear wheels to the front wheels. I don't know how valuable checking of the rear wheels is. There has been no means of adjustment on any of cars that I have owned, other than by stripdown and re-shimming, and I have never altered the settings.
I wonder if the machine will only print out the final set of readings, therefore if they do it wrong (or can't do it) they won't want to give a printout.
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This is exactly what happened in my Case 2. It was clear beyond any doubt that they couldn't set the tracking and they obviously didn't want to give me a print-out showing "out of tolerance". So they didn't press the print-out button and they lied to cover up their failure.
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I had to have my rear wheel alignment checked after seeing uneven wear beginning. Ringing around, most places I called said that they were unable to do rear wheel alignment. Kwikfit used a laser jig and realigned the rear wheels (too much toe in) and gave me a print out showing all four wheels' castor, camber, alignment and thrust angle. Uneven tyre wear was immediately stopped and the only legacy was a whine from the scrubbed edges of the tyres. Cost £60 and I got another year from the tyres. I thought it was worth the money rather than killing one pair of tyres, replacing them, and ruining another set.
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I have found that "toe-in" can be set quite successfully at home with the car on ramps using a steel tape!
The ultimate test is tyre wear. If the tread wears (slightly) more on the outside then there's too much toe-in and vice-versa, whatever the gauges say.
A common fault which I have observer at tyre fitter's is that when using an optical gauge they do not bother to move the car forward one half a wheel revolution and check again. Small variations in the wheel can make a single measurement very inaccurate when setting to less than a millimeter.
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Geoff,
I agree that simple tracking can be carried out at home with a tape measure, or two long poles, if carried out very carefully. I'm not so sure about doing it with the car on ramps though.
As I understand it, the wheels are set to a specified degree of toe-in (sometimes zero) to allow for them splaying a little as the car is on the move, i.e. it compensates for 'give' in the suspension/steering joints and mountings so that the wheels are dead parallel when under way.
Running or jacking the car onto a ramp could well put enough load on the joints and mountings to give a false toe-in reading. The tyre wear pattern will show this up, but it's a bit too late then!
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Dizzy
That's exactly the purpose of toe in. I believe some FWD cars even use toe-out, as the torque, combined with the suspension design pulls them in.
I was taught to check toe-in using an optical gauge and a set of 'Weaver Boards'. These are a pair of double plates, the top plate free to swivel on the bottom. Running the car over them causes the toe in of the wheels to swivel the top plate.
First centre and lock the steering wheel, then run the car back and forth on the flat surface. Check the gauge is zeroed!
Measure the toe in. If it's wrong, centre the weaver boards, and run the car over them.
This moves the top plates, and you can see how even the toe in is. Adjust the toe in appropriately, run the car back and forth by hand and recheck the toe in.
Repeat until toe-in is correct and also that it's even on both sides.
Takes time, but when I had access to the kit, tyre wear was never a problem.
Even if toe-in is correct first off, still check with the weaver boards, adjusting as necessary.
This was few years ago, and the teacher was one of the 'old school', and the usual comment these days is 'Whats a set of Weaver boards?
I've found it difficult getting across the need for toe in to be evenly distributed to each side at some tyre places, plus I've asked for the car to be run back and forth betwen adjustments to let the suspension settle, and been considered picky!. Takes too long I suppose!
Regards
John S
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I found this website with excellent descriptions of why wheel alignment is so important.
www.rctek.com/handling/index.html
Thing is....its about model cars and is better than any explanation i've seen about the real thing!
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Nostalgia, Nostalgia. Yes John, those "Weaver boards" were a splendid device, made by Weaver Engineering, subsequently becoming the Kismet Equipment Co. Also, with the Dunlop (A30 model?)optical wheel alignment system, mentioned by Dizzy, which was cheap and very effective, many garages were able get good results, in the fifties, on the ever increasing problems brought about by the changes in vehicle design, ie, independant suspension, front wheel drive, and radial tyres.
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Another point to bear in mind before checking or adjusting wheel alignment is that all steering joints, swivels. kingpins, wheel bearings etc should be in good condition. Tyre pressures should be correct and some manufacturers recommend loading the vehicle in a particular way.
It's a waste of time adjusting the tracking if all thats being adjusted is a bit of lost motion in a track rod end or wheel bearing, for as soon as the car is moved, the lost motion reappears - and needs readjusting.
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Slightly off topic here - my Laguna has a slight pull to the left, but when driving in France behaved perfectly. I assume this is because driving on the right, the camber of the road pulls in an opposite direction.(or maybe car was homesick). Do factory settings take this into account?
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Camber of the road is an excuse often used for pulling to the left.
On a road with a normal 1:40 crossfall or camber then a car with good steering design and condition may eventually drift but it will take hundreds of meters.
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My Wife's MkIV Golf has always pulled to the left since new..tracking has been laser aligned twice. VW insist that the settings are correct and have once paid for the laser alignment and camber setups (none found to be appreciably wrong).
Front tyre wear is even and they are only now starting to show wear after 24,000 miles.
I took the car to a newly built and asphalted large open-air car park that appears billiard-table flat and smooth: the car drove absolutely dead-straight even with hands off steering wheel. This was the same under heavy acceleration and braking.
My conclusion is that the Golf IV is sensitive to road camber.
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I need to find a similar area of tarmac to test my Mundano, but at the moment I believe the same to be true of it as your Golf. It certainly doesn't pull left in France!
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My Wife's MkIV Golf has always pulled to the left since new ........
Try swapping the front wheel/tyre assemblies side to side and see whether the direction of the pull alters. I had a car which pulled one way (the direction depending on which front wheel/tyre was fitted on which side) and eventually the dealer agreed the problem was tyre related. They fitted a new set of tyres of a different make and the problem disappeared.
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I recall these 'Weaver boards' being called 'scuff plates' (I assume they are the same thing). I took a Maxi to the Leyland dealer about 20 years ago for misalignment correction. They got it right, but told me that the opticals weren't working, and the scuff plates were faulty, so they had used their big calliper rods.
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I think manufactures are simply not doing the alignment properly.
I had new VW (02) beetle from manufacturer and after 10k tyres were shot and when taken to Kwik Fit the guy checked the alignment and they were off by 2-3mm.
Same story with BMW 3 series (07), after 18.5k rear tyres were done [expected], but front had 6mm treat at inside and only 0.25 on outside. Alignment again done by kwik fit and fixed.
I don't believe the pinkfluffy dice from BMW/VW and prestige dealers about their processes being too complex for other garages to do - its just a spin to get you to avoid going elsewhere.
The proof is in the pudding - if they don't do it right the tyres will wear incorrectly.
Also I have noticed main dealerships rarely check tracking when they replace tyres. VW failed to do so and also failed to do brake check (contrary to what they said) which I found out by going independent for 2nd opinion.
I can't fault Nationwide garages and kwik fit.
Edited by Pugugly {P} on 20/01/2008 at 10:25
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With a conventionally sprung car, if the wheels are tracked up with the car empty, as soon as the driver gets in, the alignment changes, the same goes for any changes in weight - so much for precision alignment.
The only cars which dont suffer from this problem are those with self levelling suspension, primaraly Citroen hydropnumatic. I have tracked the wheels up on CXs, BX, and XMs for the last 20 years or more using nothing more than a length of threaded rod slid inside a length of steel electrical conduit tube. It takes only a few minuets to do and produces accurate enough tracking to give me evenly worn front tyres lasting in excess of 30k miles on the XM.
Admittedly, it would not be easy to do this with the vehicle on the ground, I have a 'half' ramp which allows me to get the car to waist height, I can then sit on a box which permits me to comfortably see and adjust the steering.
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