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Thread ID: 81380	2007-07-25 22:31:00	Wheel Alignment Question	allblack (6574)	PC World Chat

Post ID	Timestamp	Content	User
572764	2007-07-26 02:01:00	So, did you test the alignment? I've heard all sorts of stories about Beaurepaires, and they charge a lot too for such crap service. Test? Guess so. Car feels no better or worse to drive. I've always avoided B/R before for that reason. This is the first time I've used them. Got numerous quotes, and this particular store gave me a good price, AND were the only one with the tyres in stock. That coupled with the FlyBuys meant they got the business.	allblack (6574)
572765	2007-07-26 02:06:00	OK . . here I am Wheel alignment is possible in a very short time if they have the newer racks with the computer system . Some shops do a "peanut butter" alignment where they drive the vehicle onto the rack and leave it there for a while and just drive it off again . The customer will never know for sure if they did anything or not . It doesn't matter if the tires are bald, bent or even missing . . well, maybe not missing . . . . for an alignment to be done on the newest systems . The machine compensates for any irregularity it discovers and will make adjustments accordingly . The old days of comparing the alignment with using the tire carcass for the measurements are all gone now . Your vehicle is front and rear alignable . . so it should be done with what we call a "thrust-angle" or "drive-angle" alignment . Balancing is an absolute must for any tire . . . and it doesn't matter if the alignment is right or not . A tire out of balance will set up a vibration usually at about 49-52 mph for a 15", 44-48mph for a 14 incher, and around 39-42 for a 13 inch tire . Those are just guidelines, but indicative anyway . Alignment includes KPA or kingpin angle, and is a throwback to days when vehicles actually had kingpins . It is the straight line drawn thru the ball joints (if there is an upper and a lower ball joint) and the angle that line generates when the wheels are turned from full left to full right . The caster if figured by the extension of the KPA where it intersects the driving surface (road) and that point is measured from there to the center of the tire tread where it rests on the road . It should be slightly negative to cause the wheels to return to center when you let go of the steering wheel and the vehicle is in motion . On a 14 inch tire, we usually see about a 1 . 5 inch to a 2 . 0 inch value . The camber is the angle that is generated by the inclination of the wheel from a flat flanged area to the flat ground and the angle is expressed in degrees . Most vehicles require approx . the following numbers as a general example: Caster = . 5º to 1 . 75º, but we usually spot this in inches rather than degrees . Camber = about - . 5º- to +1 . 0º for a rear wheel driven vehicle, add about + . 5º for front wheel drive . Toe is usually decided upon by the placement of the cross shaft or the tie rod . It is always in inches or hexa-deca-mega-kilo-meters if you are metricated . If it is BEFORE the kingpin or ball joints (also the strut mount in those type systems) then you set it at about . 5º out, and if the tie rod is BEHIND the kingpin etc, then you set it at . 5º in . The thrust of the drive against the steering is what determines the amount of toe, either negative of positive . This of course requires good physical conditions on the hardware of the tie rod ends, pitman arm and idler arms, if it is so designed . Unbelievably, alignment can be done with very bad ball joints as they "rest" in a static position and the adjustments can be made while they are at rest . If you have McPherson struts, then you must have good mast bearings and a decent physical condition of the strut . . . but not in matters of shock absorption . That is a whole different bird . Normally the toe is set about 1/8th inch to 3/16th inches toe in . Some facilities add a little toe out toward the crown of the road (the center of the road) to help keep the car climbing up to the center of the road and away from the curb or gutter side . Unless you have the alignment seriously out of whack, you'll not notice any problems with pull or thumping of the tires . The tires will WEAR out very prematurely though for an alignment issue . Tires that sing or squeal just driving straight ahead likely have the toe out of adjustment by a LOT! . Toe is the worst offender of tire wear, followed by caster . Camber is usually not too much of a problem and if it was out far enough to cause untoward tire wear, you'd be more than able to see it with the naked eye . Any thumping at a certain speed is almost always a balance problem, not alignment . A tire that is out of round or defective is another story all together . It will wobble at slow speeds or cause a hop or shimmy to the car like on a smooth surface . Many times a tire is delaminating itself because it has been rotated into the wrong rotational condition . Radials are more than likely to do this if they are on the verge of falling apart and have been rotated as the tire shops want you to . Tire rotation is a rip-off . If you have a tire wear problem it is almost always a mechanical cause and then you should repair the reason for the problem and leave the tire where it is . A bad wear pattern will not drive out of a tire and moving it without making the repair will just ruin the next tire put in that position . If you rotate all the time, you just need to replace four tires all at the same time . That's good for the tire merchants . . bad for you . With the possible damage to a tire from rotating it and the rapid wear that happens when you put a tire into a different work description, you;ll also wear them out faster . . . it's not worth the expense of the rotation that way . Ummm . . . thanks SJ . Informative and waaay-over-the-top as usual! :D But did I miss you answering the question? Can they do the alignment BEFORE removing the wheels to change the rubber? Every car I've had new tyres on the alignment has always been done after the new rubber is put on . . .	allblack (6574)
572766	2007-07-26 02:47:00	Test? Guess so. Car feels no better or worse to drive. Point it straight ahead while driving. Preferably not in heavy traffic or on the highway. Let go of the wheel. Does it veer to the left or right? It shouldn't.	pctek (84)
572767	2007-07-26 03:03:00	OK..here I am ...... always a pleasure :) when the guys do my vehicles alignment they leave the tires on (the lazer/light units clip onto the rims) and the front tires sit on a pair of moving plates so they can move the wheels while still having full pressure on the suspension system. if they took the tires off to do an alignment then there would be no pressure on the suspension and all the angles would be all over the show. eg you would be trying to set the angles while the suspension is at full height rather than halfway down as it would be when your driving.	tweak'e (69)
572768	2007-07-26 03:06:00	it's tyres	sam m (517)
572769	2007-07-26 03:11:00	it's tyres :lol: :lol: who wanted to create that poll on who has the wrost speeling? :p	wratterus (105)
572770	2007-07-26 03:32:00	Not a spelling mistake, just spelling choices. :cool:	sam m (517)
572771	2007-07-26 04:12:00	Point it straight ahead while driving. Preferably not in heavy traffic or on the highway. Let go of the wheel. Does it veer to the left or right? It shouldn't. It doesn't. But then it didn't before. All seems good, so I'm not complaining. Just wondering about the veracity of his claim....	allblack (6574)
572772	2007-07-26 05:18:00	All seems good, so I'm not complaining. Just wondering about the veracity of his claim.... You must be a Target junkie too then. :D	FoxyMX (5)
572773	2007-07-26 06:21:00	Ummm . . . thanks SJ . Informative and waaay-over-the-top as usual! :D But did I miss you answering the question? Can they do the alignment BEFORE removing the wheels/whielz to change the rubber? Every car I've had new tyres on the alignment has always been done after the new rubber is put on . . . I know . . ask me what time it is and I'll tell you how to build a watch . . . ahem! Yes . . they can align with old, new or a mixed bag of tires/tyres on the vehicle . . . the machine doesn't use the tires/tyres for reference anyway . . . just the rims/ryms . But get this part . . . . . Even if the rims/ryms are out of round (within limits) the machine will find it and compute the amount of the run-out into the computation for the correct alignment . Truthfully . . the best alignment is with the driver in the seat, 1/2 tank of fuel/petrol and the engine running to remove pressure from the dynamics on the tires/tyres at rest . . . but that's 'way over the top too . Tire/tyre pressures/presyurz were important in the old/olde days too . . but not so much any more . If the tire's/tyre's got SOME air/ayre and it isn't actually flat, there are compensations that can be made . 4WDs are just as touchy as two-wheelers/wheelerz for alignment . . . they just offer a different set of values to compensate for the 90%/10% driving characteristics of the vehicle . The manufacturers figger that you will use all four only about 10% of the time and they design the suspension and specs accordingly .	SurferJoe46 (51)
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