The move follows complaints from customers that cars had moved with the handbrake applied, and comes nine months after Fleet News first revealed the problem.
Last summer Ford issued guidance to drivers on correct application of the handbrake following incidents where it had failed to keep cars stationary.
The company denies there is a fault and maintains that in cases where cars have moved while parked the drivers had failed to apply the brake correctly.
A Ford spokesman said: 'We had complaints from a handful of customers who reported they had applied the handbrake and experienced movement afterwards. We have found that while there is no fault with the handbrake mechanism, the handbrake needs to be applied fully.'
He added that dealers would now adjust the handbrake to eliminate the risk of the car moving while parked.