I know this isn't a diesel-specific question, but you guys are so much better about answering my questions than are the other forums!

(On a W124 specifically,) what causes the steering to self-center after a turn? Is that a function of suspension geometry (camber, caster, toe, etc...), the steering box, a combination thereof, or something else entirely? I am trying to wrap my mind around how centering works.

Thanks!

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1992 300D 2.5T
1980 Euro 300D (sadly, sold)
1998 Jetta TDI, 132K "Rudy"
1974 Triumph TR6
1999 Saab 9-5 wagon (wife's)