A lorry shed its pallets and was causing 60 minute delays between Junction 6 for the Spaghetti Junction and Junction 7 for the A34 and Walsall.
National Highways say recovery is now in the final stage of recovery around Junction 6 and 7, with officers on the scene.
Congestion has now eased and the delays are now around 20 minutes.
There are also huge tailbacks through Birmingham City Centre, Perry Barr, A38, Aston and surrounding areas north of the city centre, caused by the closure of two lanes on the M6.
A separate broken down lorry shut two of four lanes between Junction 8 for Great Barr and Junction 9 for Wednesbury.
This incident has since cleared but has contributed to delays.
Road users are advised to expect disruption and to allow extra journey time.