I do both my Morgans myself. The 4/4 I can can now get within spec by eye, as oddly enough, the handling is better with the wheels fairly close to the maximum permitted toe in, and visually it's quite easy to see.
I made a crude gauge for the three wheeler, as correct alignment is quite difficult for various reasons. Not least the fact in order to make any adjustment, you have to take a steering joint apart!
Despite both steering systems being broadly similar to that used by a Land Rover, when I last used (years ago) a tyre place (a national) to check the tracking on the 4/4 they were thrown into such confusion that when I was prepared to get my hands dirty, they let me use their gauge and tools. Somehow I rather doubt it would happen nowadays!
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The tyre supplier I use (Micheldever Tyres) charges £20 for a four wheel alignment and both times I've had tyres fitted recently, I've known the cars have needed it due to the wear patterns on the old ones.
In both cases I got a full printout of before and after settings (compared with the manufacturers spec) and both times I've seen them actually doing the work. Both cars felt much better afterwards, particularly the Mondeo which felt like 50,000 miles had been taken off the steering gear.
I wouldn't bother attempting it myself, personally.
Cheers
DP
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I can endorse the good and accurate service provided by Micheldever Tyres. As long as you can time your visit to minimise the queue, the results are worth the wait.
659.
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After having a very poor 4 wheel alignment done on the quattro - they must have done the rear adjustment using standard kit but from the back of the car rather than the front with the result that the back had toe out rather than in - I chanced upon an advert in Morrisons for a set of lucas alignment kit, a bloke that used to run a garage had retired and was gradually selling his equipment (most for hgv/vans) so for the princely sum of £60 I bought the equipment.
Last time I had the alignment done on the laser 4wd thing at NE tyres in york it cost me £80.
On the thing about putting a car on axle stands, a common thing done by some race/rally teams is to set the alignment once normally with the car on the ground. Then put the car on axle stands so that the wheels are unsupported and then measure the distances wheel to wheel or make a guide as oldman suggests. Then in future they always align with the car on stands, knowing what the setting should be.
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Just a quick question, how does tracking get knocked out? If you hit a kerb/large pot hole and the tracking was affected, would something have been bent in the steering/suspension system? I guess the steering rack might move slightly on its rubber clamping, but would the suspension arms just bounce back to a normal running position on the bushes. I understand the actual adjustment is done by a thread and a locknut so that wouldnt move so that what is it that gives?
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Just a quick question, how does tracking get knocked out?
I guess in severe cases track rods may get slightly bent, but generally I would say that it is a combination of the steering rack moving slightly in its mountings plus flex in the overall bodyframe which some of the flimsy makes of cars may be more prone to.
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I was taught many years ago that it's absolutely pointless tracking or retracking a vehicle unless a full check of all steering components is made. It made sense then and still does. What's the point in achieving micron accuracy if all that's being moved during adjustment is play in a worn bearing or ball joint ? As soon as the car is moved, the free play will alter the measurement. And free play or 'compliance' is built in to many modern suspension systems.
To be honest, in all of my 45yrs as a mechanic, I've never had to adjust tracking as a service item. If it suddenly needs attention - something else is wrong !
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>>What's the point in achieving micron accuracy if all that's being moved during adjustment is play in a worn bearing or ball joint ? As soon as the car is moved, the free play will alter the measurement.
Rather tight measurement none,but you cannot get true accuracy whatever you use,certain amount of play exists in all joints, but as long as the tracking is done in a manner that makes both sides equal rather than one side only being partially adjusted and other side more so.(as often is the case with some places)
the more likely the tracking will be as accurate as you can be
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Steve
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The Fiesta seemed to track fine until I replaced the front lower arms due to seriously worn/cracked bushes. The new, firm bushes clearly held the arm in a completely different location to the perished, floppy old ones and after the job was done, the car pulled to the left.
I recall something similar after replacing the TCA bushes on my old Sierra.
I agree it is not a routine operation, and setting up tracking with worn components (as had clearly happened on this Fiesta) simply means it has to be done again when the fault is finally corrected.
Cheers
DP
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I recently changed two steering rack end ball joints and a suspension arm recently on my Mitsubishi Galant estate for an MOT (Warrant of Fitness here in NZ). Despite being careful to wind the ball joints onto the rack ends exactly the same number of turns as the old ones, my front wheel alignment was well out. The vehicle testing station had a machine at the end of the testing lane with a movable floor pad that showed the amount of slip in inches per mile. The tester nearly rejected the car again, but accepted my assurances that a wheel alignment would be carried out as soon as possible.
The tyre dealer that carried out the alignment had a machine that measured all of the alignment values, front and rear. After adjustment, they were checked again. A full-page printout of all the values of castor, camber, toe-in and some others was produced, showing the toe-in corrected from one degree of toe-out to zero degrees (specification). The cost for this was NZD 65.00, which is about UKP 15. I'm sure that a Wilko's clothes prop would work for some cars, but on mine, there is only clear access from one rim to the other for a distance of about six inches above the ground. Measuring the distance between the rear and the front of the rims is impossible. OK, a giant pair of outside calipers might do it. Also, with the clothes-prop method, apart from counting threads on the rack-rod ends, how do you know whether the adjustment is the same on each side? As mentioned above, I carefully matched the number of threads, and still ended up a degree out. After doing suspension work, I think it's probably worth having a proper alignment check done.
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The track is the distance between the rims, and adjustment is the difference front to rear of the wheel. I don't see how there can be left and right tracking. What can and often does go wrong is that the two sides are adjusted unequally, so that although the tracking is now correct, the rack has been put off-centre so that the steering wheel is no longer in the right orientation.
The front wheels don't track independently - if you adjust one side, the wheels turn in a combined effect depending on where you steer.
Rear tracking is another matter, because the wheels don't steer once the angle of each has been set in relation to the bodywork.
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....in relation to the bodywork.
Really, the bodywork isn't relevant, and the alignment between the wheels themselves is what's important. Put another way, the centreline of the car defined by the line joining the centre of the front and rear tracks does not need to coincide with the centreline of the body - the body itself can be entirely non-symmetric if you wanted!
Number_Cruncher
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Here's a question then.
The alignment reports for both Fiesta and Mondeo picked up a "wheelbase difference" of 2mm.
Any ideas?
Cheers
DP
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Dont understand the question DP?
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On the table of measurements and angles that you get on the alignment report, there's an item that says "wheelbase difference", presumably comparing left with right. Both cars apparently have a difference of 2mm.
Fairly sure neither car has been pranged significantly in their lives. I was just curious, as surely these should be identical.
Bush wear maybe?
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do you mean the gap of axle to axle compared to o/s and n/s then
o<...................>o
[ o-<
o<....................>0
where o are the wheels? on each corner?
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That's exactly what I took it to mean, yes.
My understanding of wheelbase is the measurement between axles along the side of the car. One side is apparently 2mm longer than the other.
Cheers
DP
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Well as dox says then that is entirely satisfactory.
I am sure some alignement places would take great delight in frightening someone with those figures and bang a few bolts about on a ford and lose the gap,thankfully yourself is not so fooled DP
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I was just curious, as surely these should be identical.
The dimensions of no two things are identical. There is (and has to be) a tolerance on every dimension. And there are a lot of dimensions (each with it's own tolerance) which contribute to the wheelbase.
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L\'escargot.
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Distance between front and rear wheel? 2MM, dont think I'd lose too much sleep.
Wishbone bush / rear axle bush / production tollerence?
Some Renaults with rear torsion bars were built like this from the factory. R4, R5....25MM?
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2 Dirty VW diesels and a Honda with an 18 inch blade
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....in relation to the bodywork. Really, the bodywork isn't relevant, and the alignment between the wheels themselves is what's important. Put another way, the centreline of the car defined by the line joining the centre of the front and rear tracks does not need to coincide with the centreline of the body - the body itself can be entirely non-symmetric if you wanted!
Yes, I see what you mean. But supposing, to take an absurd case an an example, you pointed both rear wheels to the right by 45 degrees (but with the correct combined toe in or out), the steering would have to centre itself similarly. The car could only travel crab-wise. If you steered straight ahead, the back would swing out to the right and you would make an inadvertant left turn.
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Yes, if you put both rear wheels at 45 degrees you are doomed! - but that is true whatever datum you choose.
The essence of my point is that alignment is done with reference to datum points which aren't linked to the body of the car - until recently, the body of a car was an awful thing to use as a datum, the design, production, and assembly methods used could give you huge discrepancies in body dimensions. Now with more computer aided design, manufacture and assembly, I could imagine bodies being produced to reasonable tolerances such that you could probably get away with using the body as a reference.
Number_Cruncher
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Do I need to dispose of my hammer collection pronto then before they're worthless? I'll keep one to whack the computer with obviously ;-)
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FAO Oldman, Come back to the darkside ;-)
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