The woman was taken to Queen Elizabeth University Hospital, where she remains with serious injuries.
The incident took place on Edgefauld Road at its junction with Balgraybank Street, at around 5.45pm on December 12.
The driver of the Mercedes A180 and its occupants were uninjured.
Police are particularly keen on speaking to a woman who was walking her dog and spoke with the driver of the Mercedes.
The road remained closed for investigation for around 5 hours.
Sergeant Kevin Craig from Police Scotland’s Road Policing Unit said: “We are aware that there were several members of the public in the area at the time of the crash and would ask anyone who has not spoken to police to please come forward.
“We are particularly keen to trace a women who was walking her dog and spoke with the driver at the time, but left the scene before police arrived.
“If any other motorists who were in the area has potential dashcam footage, this would also be useful for our investigation.”
Anyone with information should contact police on 101, quoting incident 2979 of 12 December.
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