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Would really appreciate if someone could help me in the following caster angle issue. Posting from Europe (Romania) if relevant.
In December I bought a 2012 X5 E70 M50d. I immediately performed an alignment test with the following caster angle readings:

LEFT: 7° 42'
RIGHT: 7° 20'

Two days later (lucky me) I was involved in an accident, with another car ramming into my right front side. The hit was basically directly received in the right wheel. Among others, the upper and lower front control arms were seriously damaged and the tie rod was completely broken.

After all visible damaged parts have been replaced (all three control arms - one upper, the two lower, tie rod, wheel carrier, wheel hub), the alignment machine shows the following caster angles:

LEFT: 7° 46'
RIGHT: 6° 25'

The last part to replace was found to be the engine subframe. The insurance company refuses to accept the replacement by stating that the wheel alignment machine doesn't provide standard reference for the caster angles. Could anyone post these standard caster angles? So far, I only managed to find out that the service manuals only state that the difference between left/right should not exceed 30 minutes.

Much appreciated.
 

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Caster can't be changed, except with an aftermarket "kit." That's probably why BMW doesn't specify a particular range for caster. No spec' means a car can't be out of spec'. I just got my F10 aligned at the dealer and there's no spec for caster listed on the data sheet I got.
 

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Would really appreciate if someone could help me in the following caster angle issue. Posting from Europe (Romania) if relevant.
In December I bought a 2012 X5 E70 M50d. I immediately performed an alignment test with the following caster angle readings:

LEFT: 7° 42'
RIGHT: 7° 20'

Two days later (lucky me) I was involved in an accident, with another car ramming into my right front side. The hit was basically directly received in the right wheel. Among others, the upper and lower front control arms were seriously damaged and the tie rod was completely broken.

After all visible damaged parts have been replaced (all three control arms - one upper, the two lower, tie rod, wheel carrier, wheel hub), the alignment machine shows the following caster angles:

LEFT: 7° 46'
RIGHT: 6° 25'

The last part to replace was found to be the engine subframe. The insurance company refuses to accept the replacement by stating that the wheel alignment machine doesn't provide standard reference for the caster angles. Could anyone post these standard caster angles? So far, I only managed to find out that the service manuals only state that the difference between left/right should not exceed 30 minutes.

Much appreciated.
car was in spec before the accident. Out of spec after the accident.

Seems pretty clear to me. Not having a 'nominal value' doesnt mean it is OK to be out of spec on the one value they DO publish...

What happens when you replace the engine subframe, it is still out of spec, and they decide the frame is tweaked and need to total it?
 

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I requested camber in the middle spec and toe 0.02in. I got as it shows on the photo. I think there was miscommunication and they understood 0.02 deg instead of 0.02in. However, assuming this was just miscommunication, would different toe on the same axle sound like something acceptable?

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Here is how you can convert between degrees and inches (or vice versa)


Our tires (on an E70) are 29 in diameter...

So 0.02 degrees is 0.01 inch

That 0.05 degree is 0.025 inch

Almost interchangeable...but should be balanced side to side.
 

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The plot thins. I think I now know why the "Interweb's definitive alignment expert" always screws up his units.

Back in pre-historic times alignment was done with rulers. They'd measure toe by measuring the distance between the middle of the tires in the front of the tires and in the back of the tires, as shown in Aardvark's link.

Angles can be stated in various units, the most common unit being degrees. There are 360 degrees in a complete circle. The confusion comes along when you're stating a fraction of a degree. The historic way to do this was to define a fraction of a degree in angular minutes and angular seconds. An angular minute is 1/60th of a degree, and is denoted by a single quotation mark. An angular second is 1/60th of an angular minute, and is denoted by a double quotation mark.

For example: 4° 24' 16" would be equal to 4 + 24/60 + 16/(60x60) degrees, or:4.40444°.

Then convention for not confusing angular minutes and seconds with feet and inches is to always state a value in degrees even if the value is zero. So, a half of a degree would be written as 0° 30'. or 0° 30' 0".

When kanar200 told the alignment tech he wanted 0.02 inches of toe, the tech' thought "WTF? Whatever..." and went on with doing the alignment to whatever the spec's were in his computer. All the values on the screen in kanar200's attachment are in degrees with a decimal point. Some computerized alignment equipment does report angles in degrees-minutes-seconds. BMW's Kinematics Diagnosis System actually mixes how it reports angles: degrees and minutes for toe, and degrees with decimals for camber and caster.

Pretty much the first thing they teach you in engineering school is that "units matter." If you have your units ****ked up, everything's ****ed up. That's why that Air Canada flight ran out of fuel mid-flight (fuel in pounds instead of kilograms), and why NASA's probe to Mars missed the planet (yards instead of meters).

I grew up in Norfolk, Virginia. I lived a few blocks from what is now DRS Automotive, the restoration shop featured in the Motor Trend Channel's show "Fantomworks." DRS would have alignments done at Mizell's Alignment Shop a few blocks away. Mizell's was an old school alignment shop that still used rulers. I had my 1976 VW Rabbit aligned there in the 1970's.
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The reason I dont fuss about the units is that I simply want it very small but not zero.

In kanar’s case, 0.02 degrees is fine. But so is 0.05 degrees. So is 0.01 inch or 0.02 inch.

In this case, actually, units DONT matter. First thing they teach you in executive class is ‘worry about the things that matter”. (second class is ‘how to tell what really matters…’ ;) )

The actual NUMBER is less important than the balance from side to side.

And yes, Ive seen alignments done with string and chalk. Actually it was working on my M5 years ago with a great tech that gave me insights into alignments, and demystified the whole thing!

Finally, all computerized alignment machines can be switched between inches, mm and degrees- its a toggle. (Although inches/mm requires you enter the tire size…). Maybe a tech was confused? Could be.
 

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Read this thread thoroughly, finding it very informing, I had a rear left tyre chew out the inside on my E70 X5M (F-275/45R20/ R-315/35R20), suspected toe, took it in for diagnosis and the cause was indeed some poor alignment. Attaching my report for others, will get the toe adjusted to the near zero recommendation when I figure out which tyres to go with (I just let them do their thing for today out of interest but they said they would be happy to accommodate my specified settings. Going for some non RFT this time if I can find something decent. Welcoming any feedback on the report, I also noticed the specified ranges seem a little different to the one ARD provided?
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02/2012 X5 35d M57Y CPO 119K miles NOKIAN WR G3 30K miles
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This is what the tyre shop provided me. They are the largest chain in Aus and generally do a pretty good job...no idea how they pull the info
Be very careful skeptical of salesmen of parts and / or services as they want to sell what they have to sell, parts or services. Imagine a tire shoppe that also does alignments!
 

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Be very careful skeptical of salesmen of parts and / or services as they want to sell what they have to sell, parts or services. Imagine a tire shoppe that also does alignments!
I havent done the unit conversions but what part of the report are you highlighting as concern?
Here all tyre shops to alignments as part of the service. In this case they are the biggest retailer in the country, doesnt mean they havent made a mistake though...
 

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02/2012 X5 35d M57Y CPO 119K miles NOKIAN WR G3 30K miles
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I always leave unit conversions up to the student, particularly from a single length dimension to angle.

Proper alignment is essential to tyre service life. Whatta goldmine, alignment and sales.
 

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So did you spot any issue with my alignment or just curious where I got it from?well it makes sense to do both at the same place to me, especially if you want to offer warranty on tyres.
Im planning on getting some new Falkens next week and will have the alignment redone again.
 

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02/2012 X5 35d M57Y CPO 119K miles NOKIAN WR G3 30K miles
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So did you spot any issue with my alignment or just curious where I got it from?well it makes sense to do both at the same place to me, especially if you want to offer warranty on tyres.
Im planning on getting some new Falkens next week and will have the alignment redone again.
To precisely what numbers will you order the alignment, and why? Or just “Gimme an alignment!”
 

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To precisely what numbers will you order the alignment, and why? Or just “Gimme an alignment!”
WelI I already did "gimme an alignment" which is what i posted above, when i return to get new tyres fitted i will ask for the toe to be .01-.02 and camber mid spec balanced as recommended by ARD. other than that check up after 2k kms and then every 5-10km.
 

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Apologies, my car is not an X5M rather an X5 with M sport pack, I am still having trouble understanding how to translate my report to the ISTA specs, it looks like the tyre shop may have pulled down the specs for an X5M also which would be incorrect, but Im having trouble confirming, anyone able to assist?
@ard would appreciate your view, thanks

My report Font Pattern Number Paper Parallel
ISTA Font Material property Rectangle Parallel Number
 

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Apologies, my car is not an X5M rather an X5 with M sport pack, I am still having trouble understanding how to translate my report to the ISTA specs, it looks like the tyre shop may have pulled down the specs for an X5M also which would be incorrect, but Im having trouble confirming, anyone able to assist?
@ard would appreciate your view, thanks

My report View attachment 1054317 ISTA View attachment 1054318
Looks like they had used the wrong specs, I now have the correct report which shows "except x5m and M550d") but can anyone tell me if the toe and camber is correct as they use mm for the toe measurement at both shops i went to here and the report doesnt translate well to the ISTA specs?
Font Pattern Parallel Paper Number
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