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Old 01-22-2013, 10:33 AM
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bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
Join Date: Mar 2008
Posts: 25,236
Mein Auto: 02 BMW 525i M54 auto 130K
If you're in the south bay, I gotta give kudos to this shop below, which did my friend's car (I came along to watch) and the mechanic (Rich?) was fantastic (which isn't easy for me to say).

Pro Alignment & Brake (4.5 star rating 20 reviews)
2875 Winchester Blvd Campbell, CA 95008 408-370-1421

It's a mom-and-pop operation, but they have a $50K hunter machine, looks brand new, and best of all, they let you watch up close, touch things, ask questions, snap pictures, and see all the diagnostics on the screen, and, in general, be a PITA. They don't seem to mind.

They even give you the $10 Yelp discount if you simply mention that you want it to "Debbie" the counterperson, so, the $100 alignment was $90, all told (no tax).

BTW, watching him align the car (not a BMW) showed me how complex it was to manage caster, camber, and toe simultaneously!

From memory, what he did was:
a) Lifted the car up and attached reflectors to all four wheels
b) Checked that the rear lined up with the front
c) Loosened up the tie rod ends
d) Then he adjusted caster and camber & toe, basically all at the same time
e) Then he put a lock on the steering wheel & centered (readjusting the toe)

The amazing thing was watching him push so hard that the car was literally shaking an inch or two on the floating wheel supports as he loosened and tightened the eccentrics.

The part that struck me was how every adjustment affected the other two adjustments (which I could see in red and green on the monitor).

Clearly, the part that would be difficult to do at home would be to measure all three simultaneously. I'm sure a home alignment can be done - but it took him an hour from start to finish while I watched like a hawk to see that he did it right, so I'm guessing it would take many times that to do the same job at home where we have to measure caster, camber, and toe separately.

EDIT: See also this ride-height measurement information from this thread:
> Replacing ATF: Do you level the car or level the tranny pan

Originally Posted by rdl View Post
Here is another suggestion for determining "level" based on ride height.

Ride height is measured from the lower edge of the fender arch to the bottom of the wheel lip. The key is to take the difference. A level car will have the fender arch front and rear differ from each other by the difference in ride height spec. For the purpose of checking transmission fluid level the absolute height is irrelevant; the higher the better for convenient access to the transmission. For instance, with my car the specs are 592 mm front and 560 mm rear; a difference of 32 mm. When the car is sitting with the front fender arch 32 mm higher than the rear arch, the car is "level." Side to side at each end should be identical of course.

In spite of what you eye may tell you, your garage floor is probably neither flat nor level. For instance, most garage floors have a drainage slope of ~ 1/4" per foot toward the door. Over an E39 wheelbase this works out to 2.3 inches or 59 mm difference in height. Similarly, side to side level isn't necessarily so level either, or flat. You can easily check. Pour a pail of water on your garage floor and watch it run/drain toward the door and likely puddle in some spots. Draining => out of level. Puddling => not flat.

An easy and accurate method to check relative heights both end to end and side to side is a water level. All it takes is a ruler, a length of clear tubing, a few cups of water and perhaps a funnel.

FWIW, I wouldn't worry about being "out of level" by +/- 10mm or so. It's within TIS specs for ride height differences and works out to 0.20 deg front to rear, 0.38 deg side to side. One likely has more difference from "level" due to relative settling in the engine and transmission mounts. It just won't make any practical difference in the fill amount.
Please read the suggested threads and add value, either by pictures or by descriptions, so the next person stands on your shoulders.
See also: E39 Bestlinks & How to easily find what you need

Last edited by bluebee; 02-03-2013 at 12:17 PM.
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