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Wheel alignment runout compensation

engineer2

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Dec 13, 2009
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Chicago burbs
Back in the day, when you did wheel alignments you would mount your alignment heads to the rim, jack the car up and do wheel runout compensation before you got any valid readings.

The last time I got wheel alignments, they didn't do this step. Do the new alignment machines compensate without jacking and spinning the wheels or was the mechanic just lazy? One appeared to be the latest Hunter machine with optical targets and the other was a John Bean.
 
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Schurkey

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IF (big IF) the machine centers off of a machined surface of the hub, and the wheel bearings are even reasonably tight, (or a sealed assembly) you'd be fine. We used to do that when the hub was accessible.

If you're actually clamping to the wheel rim, I'd say your shop was lazy. I can't understand how a "machine" could compensate for hardware hung off of a bent wheel, or even just attached to the wheel with some runout involved.

There's heaps of D-I-Y "alignment" equipment for sale that cannot be adjusted for runout. That's how young folks and the barely-trained think it's supposed to be.
 

kevakasper

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Feb 21, 2012
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My Hunter machine will not let you do any reading without compensating the heads first.
 
OP
E

engineer2

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We used to do that when the hub was accessible.
I remember the old magnetic caster/camber gauges. Life was easier back then.

I can't understand how a "machine" could compensate for hardware hung off of a bent wheel, or even just attached to the wheel with some runout involved.
Theoretically you could if the clamp attaching points had differential measurement abilities, but it would be expensive and not fool-proof.
 

Milton Shaw

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Feb 11, 2011
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New Hunters compensate with just a 1/3 turn of the wheel with the car never having to be lifted off the rack. The older units A111-G111 had to have the wheels off the ground and turned 180 to get the first reading and then turned another 180 to get the total and then the machine would compensate for the runout. Now they roll car back about 2 feet read and then roll forward and get next reading, this is with the new laser units with just reflectors on the wheels.
 

WhiffySpark

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Oct 22, 2009
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New Hunters compensate with just a 1/3 turn of the wheel with the car never having to be lifted off the rack. The older units A111-G111 had to have the wheels off the ground and turned 180 to get the first reading and then turned another 180 to get the total and then the machine would compensate for the runout. Now they roll car back about 2 feet read and then roll forward and get next reading, this is with the new laser units with just reflectors on the wheels.

Yup

And to add farther to that. You don't even have to roll it back to get a toe reading.

I personally prefer the tire clamp heads.
 
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Greg85mcss

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Frederick MD
X2 on the tire clamp vs rim clamp. There are steps that can be skipped or manipulated but even if you can skip compensation (I've never tried) it would be more work than just rolling the car. One thing that can be skipped & will affect your alignment is the caster sweep. If the shop gives you a printout check that there is a value in that space.


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WhiffySpark

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X2 on the tire clamp vs rim clamp. There are steps that can be skipped or manipulated but even if you can skip compensation (I've never tried) it would be more work than just rolling the car. One thing that can be skipped & will affect your alignment is the caster sweep. If the shop gives you a printout check that there is a value in that space.


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You can skip the caster sweep if you're only checking toe. We do it one f450+ all the time
 

jfcasey

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New Hampshire
Our machines you don't even have to roll back on anymore. The heads clamp to the tire and you only roll forward then do a caster sweep if needed. You can still do jacking compensation, which is still the best way if you already know your toe is way out, but it's certainly not necessary for a maintenance alignment.
 

Greg85mcss

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Frederick MD
My old shop had a machine like that. Scan the barcode, clamp the heads on & roll forward. That made for good money when it was me & a bunch of tire/lube techs. The one at my current shop takes longer to set up than to do the actual work.


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Fedwrench

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Dec 9, 2007
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Valley of the sun
The new Hunter wheel alignment machines use rolling compensation. When some of my fleet vehicles go in for warranty repair, they do a free alignment check on every car coming in the shop. They also drive over an electronic speed bump that measures tread wear in an effort to upsell alignments and tires. Technology is sweet!!!!:bounce:
 

jfcasey

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Jan 30, 2010
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Location
New Hampshire
The new Hunter wheel alignment machines use rolling compensation. When some of my fleet vehicles go in for warranty repair, they do a free alignment check on every car coming in the shop. They also drive over an electronic speed bump that measures tread wear in an effort to upsell alignments and tires. Technology is sweet!!!!:bounce:
I heard about this recently, sounds ridiculous but what do I know, haha. Our shop does the quick checks which are alright. The quick check machines seem good at sniffing out when there's a bad angle, but it doesn't always accurately nail down which axle or angle is actually out.
 
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