Supplied by dealer Rygor, the first batch of 25 medium-length Sprinter 313 CDIs is being delivered to the Wimbledon-based business.
The vehicles will be assigned to two-man crews on general utilities operations, and will often pull trailers carrying 1.5-tonne diggers. They are also being kited out with jetting units, racking systems and Hope Safe T-Bars.
Transport manager David Fahey says he took advice from other operators and rental companies, as well as trialling demonstrators, and found that Mercedes scored very highly for reliability.
"This is the single most important attribute we look for in a van because, given the service commitments we make to our own customers, unplanned downtime is something we cannot afford."
Rygor has also supplied Cappagh with 30 Fuso Canter 7.5-tonners in the last 12 months, for its tarmac gangs, and is processing orders for another 10, as well as seven 8x4 Mercedes Arocs tipper grabs.
"You'll get occasional issues with the best of products, so it's how they're dealt with that really counts," adds Fahey.
"In that respect, Rygor has been very good."