The Hoyer Group's diesel carrier came to a halt on the northbound hard shoulder at junction 16 for Stoke-on-Trent at about midday but the rear later burst into flames.
The motorway has reopened with one northbound lane closure and there are delays, said North West Motorway Police.
The driver of the tanker was unharmed.
A Hoyer Group spokesman said: "A detailed investigation will be undertaken to establish the cause of the incident and any learnings."
A fuel tanker broke down and then caught fire forcing the closure of a stretch of the M6 in Staffordshire.