Oooh! I like!

Someday, I'll get the courage up to do my own alignment.

Till then, I'll keep adding your excellent DIYs to the bestlinks:

- The dozen BMW alignment specs (1) and which are adjustable on the E39 (1) & cn90's front (1) and rear (1) home-alignment DIYs & how to DIY caster, camber & toe (1) (2) at home (0) (1) (2) (3) (4) (5) (6) (7) (8) (9) and how to make your own alignment tools (1) & the theory of alignment with (1) or without adding weight (1) (2) (3)

 

my Indy likes Heineken too
I am not a shmak, let him drink

 

Great DIY. The closest alignment guy to me is 30 minutes away, and the dealer is almost an hour. Both charge the same.

 

Amazing!
Seems complicated for me... LOL!
I usually pay around $150 for all 4 wheels to be aligned...

 

I need to update this Rear Alignment thread.
As mentioned above, one of the most difficult part of this job is the 16-mm nut way above the FRONT control arm. My longest 16-mm wrench (9.5" long) barely sticks out below the swing arm and I had to use the adjustable wrench as an "extension".

I just found out a coupling nut works perfect for this situation.
Go to any hardware store and buy 1/4-16 coupling nut for $1.00/each.
The hex side of this coupling nut fits perfectly into the 16-mm wrench!!!
Now you can use either the adjustable wrench or another 16-mm wrench for leverage.
What a beauty!

Here is what I mean:

 

May I ask the simple (possibly loaded) question of what ACCURACY is 'needed' for a home rear camber & toe alignment for the E39?

BMW specifies the following in the Bentleys (as shown in the chart below):
a) Rear camber = -2°4' ±5'
b) Rear toe = 0°22' ±4'

The allowable error translates (I think) to the following:
a) Rear camber = ±5' (i.e., from 1°59' to 2°9')
b) Rear toe = ±4' (i.e., from 0°18' to 0°26')

I must admit, I've never measured anything to a degree, let alone to four or five minutes; so may I ask what may be (painfully?) obvious to others:

Q: What accuracy is 'needed' for a rear camber & toe alignment for our E39?

 

Great Post!

This was very well done and quite helpful. Thanks! I'd like to add a few minor points.

As you noted, the front track is a bit narrow than the rear. Therefore, adjusting the rear toe to align with the fronts gives the rear wheels a little positive toe-in. According to my calcs, that puts your total rear toe-in to within specs on that car.

Also, most tires have a little bulge where they meet the ground. Wouldn't that throw your camber measurement off a bit? (Putting your level against the bottom bulge of the tire would give you a larger negative camber reading than the wheel might actually have.) So, you might have even less negative camber than you thought.

(I realize that the rear tire pressures are high on this car, and the bulge is hard to see in your photos. But still, I suspect some bulge is there -- at least a few mm.)

Again, it's a great post. I'm using it to make my alignment "close enough" after having to replace a bent control arm.

Thanks!

 

so do you need a jack or just ramps? When you are moving the camber you need to get the tires off the ground correct or do you just leave the tires on the ground at all times?

 

To make the right measurements, the wheels must be supporting the weight of the car. You can make these minor adjustments while the car in the air, of course. Or, you can do it while the tires are on the ground or the ramps (the tires have enough flexibility for you to make these small adjustments while they are on the ground).

After you make an adjustment, you can roll the car a bit (or down the ramps and then back up) to let the tires resume their normal position relative to the wheels. Then you can check the alignment again to make sure you have it where you want it. (At least, that's what I did.)

Good luck!

 

Yea that sounded like a good idea. But i was almost done when you sent your reply.... I just jacked up the car... I was messing with the bolt and seen how it functions, Then i bolted it down to where i wanted it at. But thanks for the reply

 

Excellent DIY. Im just about finished redoing the front and rear suspension (following your DIY threads ) I decided to knock the whole thing out since I needed new struts...I hate re-work and covering the same ground twice so your post is timely.

The 16mm nut on the lateral arm is a PITA to reach. I marked the eccentric washers before removing but with new control arms and bushings it will likely change.

Sent from my SAMSUNG-SGH-I747 using BimmerApp mobile app

 

A question; Most roads have a 'camber' to shed off rain to the sides... does it make ANY difference if the alignment(s) are done on a flat & level pad?

And I assume there is a difference with L & R hand drive cars?

FANTASTIC POST, THOUGH!

 

The road curve is called "Road Crown" in the US. It is designed to shed water to the sides of the road for safety reason.
This is a nice reading on this subject:

http://www.archivedsites.com/techco...com/techconnect/2011/03/getting-it-straight-wheel-alignment-considerations.html

---------
On the subject of Toe-In, Camber, Caster etc., the following was written by John Hagerman (mechanical engineer who works for the U.S. Army as a vehicle test engineer at the Aberdeen Proving Grounds in Maryland):

http://www.ozebiz.com.au/racetech/theory/align.html

 

Just in case anyone wants ideas for the proper weights, here's what I used:
- One users quest to diagnose uneven tire wear on the inside edge due to excessive and uneven alignment camber & toe (1) (2)

See also:
- Which of the dozen alignment specs are adjustable on the BMW E39 (1) (pdf) & cn90's front (1) (2) and rear (1) wheel alignment DIYs & how to keep the steering wheel (SW) straight during home alignment (1) (2) & what tools measure rear camber at home (1) (2) and what tools measure front/rear toe at home (1) & what tools lock the steering wheel & brake pedal at home (1) & the theory of alignment with weights (1) or without adding weight (1) (2) (3) & philosophically why most people prefer to let a professional alignment shop align their suspension (1) & what expensive equipment is used at the stealer to align your suspension (1) (pdf) & Internet references for how to DIY caster, camber & toe at home (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39)

 

cn90 No Runout compensation in your method!

cn,
Tons of useful information here but your method is flawed because you are missing one key item. You need to take account of the run-out or you won't be aligning the rotation axis of the wheel. (if you rotate the wheels 180 degrees and measure the difference in the position change cased by the rotation you could eliminate it.)

You can't get the measurements to +/- 5 minutes of degrees accuracy this way. (A new replacement hub I put in had 0.001 inch runnout across ~3 inch of diameter of the disk mounting plate right out of the box... that's a max of +/- 1.15 minutes of degrees error right there if I didn't do run-out compensation)

Run-out causes; machining tolerances (bearing not perfect, wheel not perfectly true) tire (shouldn't be in the equation at all) molding tolerances and deflection, crud on mounting surfaces etc. etc.

You are measuring off the rubber, how well do you think that is molded and mounted? (not well enough for minutes of degrees!) How much does it deform when you press on it? (too much for minutes of degrees!) How consistent is the pressure you apply ( not consistent enough!)

Given the massive negative camber of the e39 and your visually obvious toe problem I am sure you got it better. But it's not what you think it is due to measurement errors from not finding the run-out of each mounted wheel and using the rubber as a reference surface.

I am thinking of reducing my camber and found your post. As I said good info but flawed method. (You did consider weighting and floor level which are key too, as the geometry of the suspension moves the rotation axis as it "suspends" it at different heights.)

It's really hard to measure the "average" position of the rotation of a wobbling wheel mounted on a "spongy" suspension. If you can figure out how to do this at home let me know! This is a great start and certainly will be better than -2.4 deg nominal camber.

530 Sport

 

Thanks for the good points.

I did measure the runout on:
- Wheels ---> true and straight.
- Tires were brand new when I did this. It was also true and straight.

Re REAR Camber, so far so good 4 years later, REAR tire wear is very even, not the typical inner wear issues you see in many BMWs.

 

not the typical inner wear issues you see in many BMWs.

I had my camber set as positive as I could get away with, and my tire wear is still atrocious (about 20,000 miles).

See also:
- Which of the dozen alignment specs are adjustable on the BMW E39 (1) (pdf) & cn90's front alignment DIY (1) (2) and cn90's rear wheel alignment DIY (1) & what tools measure rear camber at home (1) (2) and what tools measure front/rear toe at home (1) & what tools lock the steering wheel & brake pedal at home (1) & why does BMW recommend weights to set the normal ride height (aka nominal suspension position) prior to any alignment (1) & how to diagnose uneven tire wear on the inside edge due to camber and toe alignment issues (1) (2) & how to select a replacement tire strictly by the numbers (1) & what are the most common bimmerfest user's tire recommendations (1) & where do people buy their tyres anyway (1) & how many miles do you get for every 100 UTQG points (1) & what are the recommended tire pressures for front and rear (1) & what are the claimed benefits of nitrogen gas (1) what tire mounting tools do you need to change your own tyres at home (1) (2) (3) & where are the match mounting marks on the wheel and on the tire for precise tire mounting based on radial runout and heavy spot considerations (1) & what tools do you need to balance a wheel at home to eliminate shimmy or vibration at speed (1) & how do you properly dispose of your old worn out car tires (1) & how to measure bent wheel dimensions such as rim runout and wheel eccentricity at home (1) & where to get bent or damaged wheel rims repaired (1) (2) & what winter driving ice and snow tire chains to use (1) & what are the most recommended products for cleaning BMW BBS wheels (1) & where to buy E39 wheels online (1) & what are the main causes of vibration while highway driving (1) & vibration while highway braking (1) & how to diagnose a violent shudder while slow speed braking on bumps (1)

 

Other Camber reduction experiences?

Has anyone else reduced their rear camber? Can you report on your resulting tire wear and handling after some miles?

I hate the inner edge wear! Also the e39 17" sport wheels and suspension seem to cause horrible tread block feathering that results in LOUD road noise for many tires in <25k miles.

 

I reduced the rear camber as much as the adjusters would allow. This was dictated by the L side as the R side had a bit more adjust-ability. Don't remember the exact number, about same place as CN90 ended up, -1.3. Handles great and less tire wear. This after replacing all the rear suspension components except the struts because they were still working well.

Jim