It absolutely could be tires, most of the pulling conditions I run into are tire related and often they are brand new.

For diagnostic purposes I would swap the tires side to side, even if they are directional. If its a tire problem the pull will distinctly change, if not then you need to re evaluate the alignment. The problem is that your car has no correction available for caster and camber as would previous MBs. A small correction can be had by using "bolt kits" strategically but they are way more of a job than a normal alignment. Because there is no alignment changes possible, anything basically in spec is accepted. On previous cars a good alignment taylored the driveability to the conditions that existed by moving caster and camber within the specs. This IS NOT possible on your car so you either have a tire problem or something different and unalignable through normal alignment procedures since the accident.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician