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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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I wouldnt, the numbers are all confusing. Really there isnt much adjustment- caster is what it is. They can really only adjust toe and camber. ¶ Say "I want minimum toe- no more than 0.02 per tire, toe in" ¶ Then "Camber should be near the middle of the BMW spec, but they must be balanced side to side- as near as possible" ¶ Write it down. Hand it to them, or write it on the work order. It is really very simple. ¶
If they pushback, point out that you just want them to hit a precise number in the wide BMW toe spec.
Thanks. I can deal with these instructions and they sound effective.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
BMW specs aren't specs at all, they are so wide/loose/sloppy that most anything will be "in spec." That allows some amateur race car driver to drive his ultimate driving machine in spec, and stingy grand-pas to minimize tire wear while "in spec." And the mechanic to make great book-money doing an alignment/check.

Yes, BMW's are intended to use a particular brand of alignment machine, that's what the little holes on BMW wheels are for, that particular alignment technology.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
I wonder how many angle notation systems there are, and who is competent to inter-convert among them.

ARD's recommendation as I express it is to 0.02° toe-in (and to which my X5 is reported to be aligned); which I believe is 1.2 minutes or 72 seconds, or best of all 0.0003490659 radian. Inches is not an angle specification, I am 74 inches tall.

I believe that the BMW dealers' alignment machine uses decimal degrees notation, which is not HMS or HMS.ss. Sorry, I forget the machine's brand.

The observed empirical effect of my reported alignment is that my oldest CPO OE t!res are about 40K miles old with useful tread life remaining, and reported flat to within a millimeter or two across their tread. I was impressed with a dealer's laser t!re profile reporting handheld device. The dealer's valet cuties run it across each t!re as the customer is making his work order.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
At the same site, robrobinette.com, I found this, ***8220;DIY Alignment Calculator * Disclaimer: Always verify the calculated values before relying on the data for any practical application.***8221;

For length and angles calculations, remember good ol***8217; Chief Soh Cah Toa. Sine of angle = Opposite length/Hypotenuse length, Cosine of angle = Adjacent length/Hypotenuse length, Tangent of angle = Opposite length/Adjacent length
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
I believe that the design normal position for alignment has the steering wheel centered.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
Here are BMW E70 Steel spring alignment tolerances in degrees° and minutes'

https://www.newtis.info/tisv2/a/en/...alignment/32-00-steering-measurement/3ldT9dbe

Your work order should be to the effect of "Align to 0°02' (0.03°) toe-in left and right, front and rear. Align camber to 0°20' (0.33°) left and right, front and rear."

The specification on the sheet is 0°14' ±12'. 0°14' - 0°12' = 0°02'; remembering that minutes' run 0' to 60'. I believe decimal degrees are less likely to be mistaken.

Note the "*Note: To minimize adjusting errors (measuring inaccuracies), use a narrower tolerance for adjusting toe / camber." A tolerance of 0°0' is narrower than the listed tolerances of ±12', ±25' , respectively for toe-in and camber.

BMW alignments are intended to be done on Biessbarth KDS systems. That's what the five little holes in OE / OEM wheels are for.
https://www.newtis.info/tisv2/a/en/...r-manuals/32-steering-wheel-alignment/1sEsgk1

There are many apps / programs available to convert among the angle notation systems; D°M'S", D.dd°, and D°M.mm' are common.

The length of one side of a triangle specifying angle is nonsense. Two parameters of the triangle are required to name the trigonometric function.

The extremes of the alignment number tolerances have very different effects - on tire wear and handling - that you must understand and have YOUR car aligned to perform as you desire. YOU are the customer and always right.

Ideally, for maximum tire life the tire should be absolutely parallel to the direction of travel to minimize squirm, but because the suspension is resilient that would allow excessive toe-out which has undesirable effects on handling - 'darty'. Ideally, for maximum tire life the tire should be flat on the road with zero camber, but because vehicles roll that even weighting is lost in every turn and practical camber is a compromise.

Best wishes.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
My replacement tires are staggered 285/35-21 and 325/30-21 rear. Somehow, even with good alignment and balancing, both rears chewed up the interior edges with only 21k miles...
front treads are fine.

So, which alignments specs do I use and need to leave it at the 'specialist' BMW dealer?
Really? for $295 cost? Seems very high, but I need this done right....

Second issue: I like high inflation, 40-42 psi, two reasons, MPG and better handling.

Third reason now, with the high neg. camber on the rear - as spec'd, an over inflated tread will round off the edges and roll more into the center for wear. Has anybody added PSI and gets better wear results from overinflation on these massive rears?

Thx Q
Mine is aligned 0.02° toe-in all around and camber left and right balanced mid-range front and rear. For maximum mileage and checked twice now.

YOU must know the effects of the extremes of the allowable alignment specification and specify the number to the mechanic.

I preemptively replaced my CPO OE at ~40K miles with about half tread remaining.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
Joined
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23,962 Posts
The principle is to maximize tire life by minimizing squirm and friction with the wheels set as close as possible to straight ahead but with little chance of more than transient toe-out; with its known problem of darting. No one that I know has ever made an objective principled argument for more toe-in. Arguments made are always subjective.

Camber is to accommodate body lean and weight transfer to the out side wheels. None will work but too much will eat tires.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
You ordered and paid for ***8220; *Minimum toe, No more than 0.02 per tire, toe in.***8221;. The only argument that they have is that you did not attach units to your ***8220;0.02***8221;

Other than than, it looks balanced and useable. What are front camber specifications for your after to be RED?
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
I use the dealer for all work, divided between Appleton and Ocala.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
My 2017 X5D X drive bought new was off. I had two dealerships realign it. After about 12,000 miles I realized my OEM Michelin RF's were going to be toast at about 20,000 miles. I went to an independent shop near me and for $150 had it properly aligned. Drives way better and the tires stopped wearing altogether. Both dealerships missed that one rear tire was way off causing it to drive oddly and wear tires rapidly. My take away, factory settings are terrible as too are dealerships. I'll never ask the dealership to align again even if they cover the first with low mileage when new.
To what numbers did you order your X5 aligned? Precisely. Before and after alignment sheets are always interesting.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
Are these the same specs for an '15 X5 (F15)? Getting new tires and alignment on Wed. I plan on walking in with the following written down: 0.02 toe in all 4 wheels, camber set to middle of the spec'd range, balanced from side to side on each axle
Yes, same specs. Be careful; 0° 1' = 0.02°
IOW ZERO degrees plus ONE minute = ZERO degrees plus decimal ZERO TWO degrees. TWO hundredth of a degree.
1018253
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
There are separate specification allowance sheets for the other suspension options. I don't know that they are different.

At a glance(!), at a glance they are not different.

The recommendation to 0.02°° toe-in and balanced mid-range camber is based on general principles and not on some peculiarity.

Hypothetically, why not align your car - or all cars - to ZERO toe and ZERO camber? What is the effect of minimum toe, what is the effect of maximum toe? What is the effect of minimum camber, what is the effect of maximum camber?

I believe that toe-OUT causes positive reinforcement of the angle, more toe-out, and toe-out causes dartiness for the positive feedback. Negative camber causes body roll in cornering to square the outside tire to the road. Of value only in extreme cornering.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
When I write 0.02° I mean ZERO degrees plus ZERO decimal ZERO TWO degrees. Two hundredths of a degree.

I told my BMW Service Center alignment mechanic “Two hundredths of a degree.”. He uses Beissbarth KDS alignment machine. Alignment checks in the years since have all been within machine error, i.e. pretty damn close.
 
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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
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23,962 Posts
Does BMW really recommend a very slight toe-out in front on an X5??Not toe-in??
E70 Steel Spring toe alignment ALLOWANCES - NOT recommendations
Front axle:
Total toe-in0° 14' ± 12'
Total toe-in adjustment*0° 14' ± 04'
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 121K miles NOKIAN WR G3 30K miles
Joined
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23,962 Posts
I think it means both sides combined. Wheels pointing very slightly inwards (Toe-in) as opposed to pointing outwards (Toe-out) on a horizontal plane. Camber would be the angle of the wheels on a vertical plane. Negative camber is usually preferred, especially in the rear.
1019846
 
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