Manufactured by bodybuilder Johnston Sweepers, the vehicles are based on Euro 6 DAF LF 220 chassis supplied by dealer Greenhous.
Go Plant specified the Allison fully automatic transmissions to reduce driveline maintenance costs previously experienced with automated manual transmissions (AMTs).
The order is part of a fleet investment of 48 new vehicles in the first quarter of 2015.
"We've upgraded to the Allison transmissions because of the reduced lifecycle costs and the improved vehicle driveline – something which inevitably suffers a high level of wear and tear during road sweeping activities," explains Aiden Garvey, regional manager for Go Plant.
The Allison torque converter provides smooth shifting even at very low speeds, he explains.
"Our vehicles need to be robust and reliable, regardless of the different drivers that operate them and their varying driving styles," adds Garvey.
"We have found Allison transmissions to be very easy to use and look forward to seeing the new vehicles on the road in July."