I have '97 E320 with 100K miles and recently noticed that the steering wheel is not centered when the car goes straight on the road. Itis turned counter clock wise about 15 degrees.
Do I need a allignment ? What exactly is wrong there?
Any help and advice would be greatly appreciated!
THANKS!

 

Hi,
At some point either
1. Your steering wheel has been removed and refitted from the steering column onto the incorrect "spline" (some models have a design that prevents this being possible) or
2. A steering track rod has been bent due to a "minor" kerb strike or accident damage or
3. A previous attempt at steering / wheel alignment / tracking has been carried out incorrectly.

When aligning the front wheels on a vehicle it is important that the procedure is carried out with the steering wheel in the straight ahead position. This position is also usually associated with the position that the steering lock but this may not always be the case. Once the steering wheel is in the straight ahead position each front wheel is then adjusted to give the correct amount of "Toe-In or Out" as indicated in the Service requirements for the vehicle. Different vehicles have potentially different settings.
Some "alignment" garages do not follow this procedure and merely ensure the INCLUDED angle between the two front wheels is correct (assuming their equipment is correctly calibrated which it often isn't!!) rather than the individual measurement of each wheel relative to the longitudinal axis of the car. This longitudinal axis of the vehicle is also defined in different ways by different manufacturers and MB have a very sophisticated way of determining this in order to reduce the incidence of problems similar to that which you are experiencing. (MB now use four wheel alignment to determine the longitudinal axis rather than the longitudinal position of the body sill panels.
A steering wheel that is out of position (for whatever reason) may also point to a steering column steering angle sensor issue since this sensor needs to know where "straight ahead" is.
IMHO once set at the factory it is best to leave "tracking" well alone because few garages have the equipment and expertise to do this correctly. Retracking vehicles every few thousand miles seems to be a USA thing. All too often a vehicle is retracked incorrectly and although this may appear to correct an initial problem...i.e. the car pulls when on the highway...the initial problem was wrongly determined and a situation of "two wrongs" making a "right" exists but leads to further problems down the line. i.e. the steering wheel isn't straight, the ESP light is on etc.

Unusual tyre wear and / or after accident damage or kerb strike are the only times that I believe it is necessary to routinely retrack a vehicle.

So YES you need to go through the complete retrack procedure since the existing installation setup on your car is an unknown and in some way incorrect.

Finalpoint.
Not sure if it applies to your model MB BUT iIF your steering wheel can be fitted to the column at any angle (i.e. no design feature = "special" spline dictates where the wheel fits it is necessary to determine when the rack or steering box is in the straight ahead position BEFORE starting to make adjustments. Racks and steering boxes usually have a feature that allows them to be locked in the straight ahead position.( e.g. introduction of an external locking pin for the purpose)

Hope this gives you a good understanding of your problem.

Good luck.

Stuart