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what weight do you put in for alignment?

102K views 50 replies 18 participants last post by  ThreeM30s 
#1 ·
I'm getting 2 new rear tires from Tire Rack, got couple alignment questions.

1) Should I do alignment at my stealership or at tire installer from Tire Rack?

I saw the following quoted along with alignment specs.

Normal weight loaded position:
Each front seat = 150 lbs.
Rear seat (center) = 150 lbs.
Trunk = 46 lbs.
Fuel Tank = Full tank
2) I was wondering if the above weight is official or
should I do alignment with what I typically have in my car
i.e. 145 lbs front (myself) , half tank (this seems to be the average of full and empty, I only fill up when empty) and 50lbs misc. stuff in the trunk.

3) I have a 2001 325Ci (no sports package) , I should still be using the spec form Sport suspension below right as I remember all the coupes have sports suspension regardless of sports package.

4) Any specific question I should ask the tech to see if he knows what he's doing.

thanks.

:thumbsup: Bim Growl , thanks for posting bently manual , if only all the pages are available online.

Boy, I wonder how many times I have to post this before people start paying attention?

From the Bentley Service Manual:




 
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#2 ·
1) Should I do alignment at my stealership or at tire installer from Tire Rack.
Depends on how you judge the relative importance of risk and money. At the dealership, you will spend more money but have a greater chance of it getting done right. An independent shop will be cheaper, but there is a tremendous amount of variation in their competence
I saw the following quoted along with alignment specs.
2) I was wondering if the above weight is official or
should I do alignment with what I typically have in my car
i.e. 145 lbs front (myself) , half tank (this seems to be the average of full and empty, I only fill up when empty) and 50lbs misc. stuff in the trunk..
The ballasting is "official" and here's an extended discussion about it - http://forum.e46fanatics.com/showthread.php?t=296171 and that plus some good general info here - http://forum.e46fanatics.com/showthread.php?t=341768

My recommendation is not put the weights in, have a full tank of gas, and empty your car any misc. junk. That way you've got an easily repeatable condition to baseline against.
3) I have a 2001 325Ci (no sports package) , I should still be using the spec form Sport suspension below right as I remember all the coupes have sports suspension regardless of sports package..
You are correct - use the sport suspension settings
4) Any specific question I should ask the tech to see if he knows what he's doing.
Ask him about adjusting the front camber. If they deny it can be done, go somewhere else. Also, make sure they've got a real 4-wheel alignment rack and don't just try to do a 2 wheel alignment in each end.
 
#3 ·
Just to make this thread more comprhensive - here's the sheets from the TIS describing the proper conditions for alignment. The interesting thing I wasn't aware of until recently is that the ballasting specs are different for convertibles. Coincidentally enough, the reduction in ballasting weight seems to correllate with the additional weight of the convertible.

Also, for those who don't think in metric, 1 kilogram is about 2.2 pounds.
 

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#4 ·
JPR , need some help

Thanks for the informative reply. long story short; got a 4 wheel alignment (not from dealer) last time with the purchase of rear tires. now (9 months later) the fronts have to be replaced due to excessive wear on the inside (inside's tread is gone , outside still has plenty). alignment was done with me (150#) at the front, half tank and some junk ~50# in the back.

The car drove fine, but now I realize the importance of a good alignment for tire wear (not just driving). I got a few more question before getting another alignment with my new front tires.

Can you confirm that WITHOUT ballasting the car, the alignment would have more (POSITIVE) camber and more (POSITIVE) toe in?

If that's the case,
and if I want to get an alignment and don't want the trouble of adding all the weight, should I go with the lower range in the spec.
for example from toe spec is (0 14' +/- 8') , so go with -8 (i.e. 0 06')

Also, can somebody explain the following from the spec
  • Toe angle total , is that just left value + right value?
  • what do the 2 numbers under front camber represent?
  • what do the 2 numbers under front caster represent?

could I expect the shop doing the alignment to have these 9 numbers before and after the alignment?

Thanks.
 
#5 ·
Thanks for the informative reply. long story short; got a 4 wheel alignment (not from dealer) last time with the purchase of rear tires. now (9 months later) the fronts have to be replaced due to excessive wear on the inside (inside's tread is gone , outside still has plenty).
As you seem to have already surmised, that appears to be a classic case of too much toe in

alignment was done with me (150#) at the front, half tank and some junk ~50# in the back.
It's good you kept track of that, but I still suggest that you would be better off with an empty car and a full tank of gas. Assuming you use car like a normal person and it's not a dedicated race car, there's really no need to have you sit in the car while they align it. If that were not the case, then every time you had a friend in the passenger seat, your alignment would be off. The reason for the empty car and the full tank of gas is that it's a whole lot easier to replicate than trying to get to the exact same half tank level and remembering just what junk it was you had in the car. The reason you want the car in the same condition is to make comparing previous and current alignments more of an apples-to-apples thing.

Can you confirm that WITHOUT ballasting the car, the alignment would have more (POSITIVE) camber and more (POSITIVE) toe in?
That's correct, but the camber change is the truly dramatic one. The toe change is pretty small potatoes, especially in comparison to the accuracy tolerance limit of the alignment machine, and you can basically ignore it.

If that's the case,
and if I want to get an alignment and don't want the trouble of adding all the weight, should I go with the lower range in the spec.
for example from toe spec is (0 14' +/- 8') , so go with -8 (i.e. 0 06')
As mentioned above, the difference in toe is trivial, but generally speaking shoot for the low end of the range. On the front, there's nothing wrong with even running zero toe, so don't be afraid to cut that way down. You'll want to be a little more conservative on the rear, as that is what helps keep the car driving straight. 0.25 deg is a good target for the back, but if you've got polyurethane bushings, you can even go a little lower to say about 0.20deg ro so.

Also, can somebody explain the following from the spec
  • Toe angle total , is that just left value + right value?
  • what do the 2 numbers under front camber represent?
  • what do the 2 numbers under front caster represent?
Here's some info direct from a BMW training manual:
Track Differential Angle with 20deg lock on inside wheel - This angle is also known as “Toe Out on Turns”. With the inside wheel turned to 20 degrees on the front turn plates, the difference in the toe angle should be as specified.

Caster - Caster must be measured by sweeping the wheel through an arc of 10-20 degrees. (Most alignment equipment requires at least 20 degrees). Ride height is crucial to this specification. If the vehicle is too high or low in the rear, the Caster measurement will be affected. Caster is NOT a “live angle”, the wheels must be resweeped to check the measurement again. Although Caster is NOT adjustable, it should always be checked to insure there is no “hidden damage”.
could I expect the shop doing the alignment to have these 9 numbers before and after the alignment?
Don't sweat it. There's really only four things they can adjust: front camber, front toe, rear camber, and rear toe. Get those right and everything else will be okay as well (so long as you don't have some sort of large structural damage you don't know about)
 
#6 ·
jpr

Thanks for the quick help, it's nice to have experts on the forumn.

sorry for being dense but for sport suspension.

is the toe in the spec expressed as left toe + right toe (i.e. total)?
for low range , I should go for 6'?

is (43' +/- 20') the (left camber + right camber when the car is pointed straight or is it just one side (i.e. just left , just right)?
for low range , I should go for 23'?

is -1 deg 34' +/- 30 the difference in toe angle when inside wheel is at 20deg?

sweeping when +/- 20 , caster should be in range of 5deg47' +/- 30?

what's front wheel displacement and geo axis deviation and do they check this in an alignment?

since you mention that there are only 4 points to tune, I'm guessing that a regular shop may not check all those 9 points. Do you know if dealer has procedures to check all 9 points?

thanks.
 
#7 ·
Happy to help -
* Yes, the toe listed is total toe. The presumption is that you split this equally left/right
* Definitely shoot for the low end of the range on the front. If it's not to your taste, it's not that bad a DIY to readjust it yourself http://forum.e46fanatics.com/showthread.php?t=459889
* There is a typo in the Bentley manual on the sport suspension front camber. It should read -43' not +43', so the spec range is actually -23' to 1*06'.
* The camber spec is for each individual wheel
* The toe out on turn feature is also known as the Ackerman angle. It's nominally and R/C car site, but there's lots of good info on that and other alignment stuff here -http://www.rctek.com/handling/toe_angle_effect_on_ackerman_steering_principle.html Also, when I get a chance I'll scan in some of the alignment info from the TIS and post it
* As far as what gets automatically checked goes, that pretty much depends on the type and vintage of alignment machine being used. But again, there's a pretty short list of things to actually put a wrench on and that's what I tend to pay attention to - part of that whole only worry about those things you can control ethic.
* As far as what to set you car at, I've got mine at -1.1deg front camber, zero front toe, -1.6deg rear camber, and 0.17 rear toe. For the whole story, check out the link below "My Suspension Upgrade"
 
#9 ·
Just like to add that I shopped around and went with cheapest dealer in the area (also happen to be closest to where I live). Before going in I verified that they do ballast the car with sand bags. I emptied the car, filled up the tank, and pumped the tires to what I normally like (32 front, 38 back). The rear tires are new and the fronts had been my rears for 9 months.

Afterwards, the dealer gave me a printed report of the before and after specs. As anticipated (see posts above), there were too much toe, and they fixed it.

Lessons Learned

1) don't mess with alignment
2) if you take it to a non-dealer shop, don't tell them to follow the specs unless you're ballasting the car and you haven't modded suspension.
3) if 2 doesn't work for you, keep detail of condition of the car (i.e. how much weight you have in it and where, full tank, pumped tires) before getting the alignment. you'll need the same condition when you get another alignment, so the shop can adjust accordingly.

Special thanks to JPR.
 
#11 ·
To keep making this thread more comprehensive, here's some good alignment and suspension info I found at Toyo Tires Australia - http://www.toyo.com.au/
 

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#13 ·
Just to keep adding to the information stockpile, here's info on BMW's alignment systems and instructions for adjusting the front and rear axles.
 

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#14 · (Edited)
One more interesting thing - according to this the Beissbarth alignment machines used by some BMW dealerships have had a software update that eliminates the need to use ballasting weights.

It's unclear whether or not this capability is shared by the two BMW authorized Hunter KDS systems, or by Hunter systems in general. My guess would be "yes" to the first one, and "only on the the most current models" to the last one.

EDIT: An interesting question I don't know the answer to is that if you have your car aligned without ballast on the Beissbarth machine, does the report reflect a converted value of the actual measurements to the specified values or does it compare the actual measured values to the conversion of the specified values?
 

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#15 ·
An interesting question I don't know the answer to is that if you have your car aligned without ballast on the Beissbarth machine, does the report reflect a converted value of the actual measurements to the specified values or does it compare the actual measured values to the conversion of the specified values?
The answer to this question, courtesy of TX who sent me his alignment report, is that the machine reports the actual measurements and converts the spec values to compensate for the actual undballasted ride height.

This is for a non-sport alignment, but there's some interesting things to note -
* there's no significant change in the front toe setting
* you do need to add a hair more rear toe to an unballasted alignment to make it equivalent to a ballasted alignment
* on the rear camber 1.15deg unballasted is about 1.50deg ballasted
* unballasted front camber was actually a little bit more than ballasted since the ride height was slightly lower as the nose was slightly pitched down without the ballast weights.
* Now your actual results may vary depending upon your fuel load and whatever junk you've got in the car. The important thing to note is the ride height comparison at the top of the page.
 

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#17 ·
Here's another example of an unballasted alignment done by a dealership with the updated KDS that changes the spec values to compensate for the actual ride height.

In this case, it's a sport alignment and as with TX's alignment, the car's unballasted ride height is slightly nose down, but the rear is sitting about 20mm above the design value as compared with TX's non-sport being only 10mm above the design value. Consequently, there is little change to the front specs, but a rather substantial change to the rear:
* The unballasted rear camber spec is shown as about -1*15' compared with the ballasted spec of 2*4'. (that's -1.25 vs -2.07 if you prefer)
* The rear toe spec is at 0*19' in comparison to 0*16' ballasted (0.32 vs 0.27)

Alignment report was found in this thread - http://forum.e46fanatics.com/showthread.php?t=425409
 

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#20 ·
thanks. also read your thread about the weight one should put in. these were the recommended weights, right?

Normal weight loaded position:
Each front seat = 150 lbs.
Rear seat (center) = 150 lbs.
Trunk = 46 lbs.
Fuel Tank = Full tank


how important is it for the tank to be full for this? can i just make up with more weight in the trunk instead? the tank holds, what, 15 gallons? so if 1 gallon of gas is 6.1lbs(according to my research), the total weight in gas should be 91.5lbs total for a full tank of gas. thanks for your help :thumbsup:
 
#23 ·
jpr, I have a o4 m3 where the ride hight is quite high at 627 -627 mm in the front and 612- 614 mm in the back with myself and a full tank of gas.the shocks,bushings all look good but this car has extreme wheel hop under hard acceleration ,what alignment settings might help this,could this be a geometry problem with the ride hight being so high?
 
#24 ·
The ride height will be function of the springs and the weight of the car and the geometry consquentially affected by that, rather than vice versa. While you car seems on the high side, it does still seem to be in the "normal" range. My guess would be that you've got a somewhat lightly optioned M3.

As for the wheel hop, when exactly does it occur? Corners, straights, certain speeds/gears?
 
#27 ·
Trolling back through the TIS again, I do believe the proper official ballasted condition for aligning an M3 is with the weight in the front seats and trunk.

If you look at the attachment in this post - http://forum.e46fanatics.com/showpost.php?p=6832509&postcount=14 - it states "Note: Only check E46 M3 in normal position"

"Normal position" in BMW parlance is the ballasted condition. See the attachment for the M3 entitled "Wheel Alignment - Normal Position / Inspection Conditions E46 / M3 / M3 CSL"

"Design position" is another term that has a specific meaning. Basically, it starts with the loading the car to the "normal" position then moving or adding (but not subtracting) weights until the ride heights at the wheels are within 1mm of each other.
 

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#30 ·
jpr i was wondering if you might have the official TIS for the m3 differential as for inspection for proper operation and how to measure to determine what is allowable amount of back lash in the m lock diff? The reason being the m lock diff has a little hydralic pump in it that may be faulty giving improper power transfer and slip. I believe there is a special procedure to change the oil in these diffs if not done correctly that might lead to the sensation of wheel hop?

tia
 
#31 ·
I cannot find any documentation regarding any of those issues.

The closest I've seen is an advisory to only use MSP/A fluid in the LSD's otherwise a "creaking noises" can be heard while the car is in motion. That advisory however, dates back to 1995 so it's not exactly an E46M3 specific issue.
 
#35 ·
I got my alignment done today at an independent shop, they used a John Bean machine. It feels great now, I had to talk/argue with the tech to get the correct measurements. He did not even know, I had a sport pkg, luckily I came back there to check.

Thanks for all the info JPR, they thread have been wonderful. :thumbup:
 
#37 ·
My alignment values, there's still a slight pull to the left. But it is much better than what I've had. Let me know your insights
Looks pretty good. As for the slight pull remaining, my first guess would be that it's a residual effect from uneven tire wear under the prior alignment. If you are feeling energetic, you could swap the left and right rear wheels and see if the pull swaps sides as well.

(It's also worth clarifying just what you mean by "pull". I'm assuming you mean that when you take hands of the wheel the car naturally drifts to left. The other possible interpretation is that to when you take you hands of the wheel, the car drives straight but the steering wheel is not centered. The former is generally a rear toe issue and the latter a front toe issue.)
 
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