The Highways Agency will be carrying out safety improvements on the M621 next week.
Work will take place to replace the steel central reservation barrier between junctions three and four with a concrete barrier.
The new concrete barriers are stronger and reduce the risk of vehicles involved in accidents crossing from one side of the motorway to the other.
Motorists are being advised that from Monday, between the affected junctions, the speed limit will be reduced from 50mph to 30mph until October 22.
During the work there will be night-time closures of the clockwise and anticlockwise carriageways. Only one direction will be closed at any one time, with a lane two closure in place on the opposite carriageway. All lanes will remain open during the day.
Work will take place overnight and will start at 9pm each evening. The work will finish at 6am Monday to Fridays, 8am on Saturday and 10am on Sunday mornings.