DLKW has been given the task of developing a press campaign and created the ads currently running in national titles using the strapline: "The strong, silent type."
In the past, Vauxhall has held a roster agency pitch for each of its car brands, passing all the resulting work to the winning agency.
It is not certain if a pitch was held for Vectra, but DLKW is now expected to take the lead on the business.
The Vectra brief is one of Vauxhall's most prestigious. Lowe's most recent work for the brand was a high-profile 2002 TV ad campaign featuring the Hollywood actor Ed Harris (the star of Pollock and The Truman Show). Cast as a lawyer, Harris aimed to prove Vauxhall's claims for the car and to differentiate it from its previous model.
Lowe also created the Vectra launch campaign featuring helicopters delivering the cars to the tune of The Verve's Bittersweet Symphony.
The win continues the inroads DLKW has made on the £51 million Vauxhall account since its appointment to the roster in 2002. The agency, in which General Motors' holding company, Interpublic, has a minority holding, was appointed to the relaunch of the Astra earlier this year, after a pitch against Lowe. It also swiped the £10 million dealer account, previously held by Lowe Broadway.
Lowe's hold on Vauxhall extends to Zafira, Signum and Vauxhall Vans.
It also won a pitch to launch the Tigra against DLKW in February.
The win does not affect media planning and buying, held by Initiative Media.
Lowe refused to comment.