The latest phase of a multi-million programme of safety barrier repairs gets underway this weekend.
And it will see the closure to most vehicles of the northbound on-slip to the bridge at the 'Spectacle Roundabout' A726/A898.
The diversion, which will remain in place until next year, means the journey from Erskine to Clydebank, about 6.5 miles, will involve an almost 15-mile drive.
All motorway traffic will be diverted via the A726 to M898 southbound on-slip then onwards to the M8 westbound to Junction 31 at Westferry before returning eastbound.
Any non-motorway traffic faces an even longer diversion to the Clyde Tunnel before returning on the A82 westbound.
The project is being carried out by Highway Barrier Solutions (HBS), on behalf of Scotland TranServ.
The work will replace the existing vehicle barriers with new ones that provide increased protection for the bridge's main supports.
Traffic management arrangements mean that, between September 14 and 15, a contraflow system will be in place to allow the installation of a temporary barrier.
Scotland TranServ is warning that it expects delays of up to 60 minutes between 11am and 6pm this weekend.
From Monday, traffic on the bridge will be reduced to single file in each direction, with a temporary barrier system providing protection for road workers and motorists alike.
Delays of around 30 minutes are expected during peak hours for the full ten months of this scheme.
To improve traffic flows across the bridge and on nearby roads, the northbound on-slip from the 'Spectacle Roundabout' will be closed to all vehicles except buses, works traffic and emergency vehicles. On the north side, newly traffic lights will be in operation on the A82/A898 on-slips.
Russell Rennie, contract director for Scotland TranServ said: "This is a vital project to upgrade vehicle barriers across the length of the Erskine Bridge, ensuring they meet modern safety standards.
"This in turn will ensure the safety of motorists travelling across the Erskine Bridge for years to come."