Police seized £1.36 million-worth of cocaine from a car at Tebay Services.
Lancashire Constabulary stopped the vehicle on Thursday and found 17kg of the drug.
Officers arrested two men on suspicion of possession with intent to supply class A drugs.
Scott Chadwick-Greer, 30, of Oak Avenue, Thornton and Stephen Buckley, 39, of Lancaster Avenue, Thornton, appeared at Preston Magistrates Court on Saturday and were remanded in custody.
Two women, aged 35 and 31, were also arrested on suspicion of assisting an offender and have been bailed pending further enquiries.
The M6 was closed for a short time while police dealt with the incident.
