Dennis SS series  The Dennis SS series is a fire engine built by Dennis, it was produced from the early 1980s until the 1990s. The Dennis SS was almost identical with the previous RS model. It incorporated the same cab design, engine and transmission, except the SS (Split Steel) had a tilting cab which made maintenance and overhaul much easier. It could be fitted with a variety of bodies by Dennis and other coachbuilders such as JDC, Carmichael and Fulton Wylie. Even though the cab design of the SS dates from 1978, they are seen to this day in fire brigades throughout the world, with many still in front-line use. In the later years the SS series appliances were dogged with door corrosion, aptly known as "Dennis Disease" as almost every single SS appliance suffered from rotten cab doors at some stage in their lives. Several variants were built. The earlier models (SS130-SS137) were powered by Perkins V8 engines, with both manual and automatic gearboxes. Later models (SS233-SS245) were powered by Cummins diesel engines. Most appliances had Kirkstall and Eaton axles fitted, front and rear respectively, some with limited slip differentials. All chassis came with a choice of 500gpm or 1,000gpm fire pumps, depending on application. Whilst successful worldwide, the series was most popular in the UK and Ireland. Most UK brigades bought Dennis SS appliances.