All four occupants of the Audi A4, which fled the fatal crash scene, were released on Tuesday evening.
Police released three men, including the driver, under investigation pending further enquiries. A woman passenger has also been released without charge.
Two men aged 22 and 24, both from Wakefield, a 21-year-old woman from Abergavenny and a 24-year-old man from Ossett, West Yorkshire, were released after being arrested on suspicion of causing death by dangerous driving.
David and Patricia Howard, from Lancaster, died following the multi-vehicle collision close to junction 31a for Fulwood at around 9.55pm on Sunday, November 11.
An Audi A4 travelling northbound collided with their Vauxhall Vectra, which hit a Volkswagen Transporter, which then collided with a Citroen CX Athena.
Emergency services attended and Mrs Howard, 58, who was driving the Vectra, was pronounced dead at the scene. Her husband David, 57, was taken to Royal Preston Hospital, where he died a short time later after suffering catastrophic injuries.
The occupants of the Audi made off from the crash site before police and emergency services arrived at the scene. All four occupants were later arrested by police in connection with the incident.
The driver of the Volkswagen, a 47-year-old man from Ulverston and the driver of the Citroen, a 70-year-old man from Galgate, were not injured.
The road was closed for more than six hours while accident investigators attended the scene.
An 18-year-old woman was initially arrested by police but has since been taken to hospital having suffered a broken arm.
Police are continuing their investigations and are appealing to the public for information.
Sgt David Hurst, of Lancashire Police, said: “We are appealing for information following the collision and if you saw what happened and have yet to speak to police, please come forward."
Anyone with information can contact police on 101 quoting log reference 1407 of November 11.