The GMC Topkick are one of the best heavy duty trucks available in many markets across the world today. However before you finalize one of the many models available under the Topkick brand you should find out the exact purpose for which you will be using the vehicle.For example, if you want a dependable medium duty truck then you can go for the C4500 model or the C5500 model. These two models can be used for several types of jobs such as delivering material to landscape sites and light construction jobs. The customized models under these categories include crew cab models, fire and rescue cutaways and also school bus operations. The engine is normally the Vortec 8100 V8 gasoline engine which lead to decreased transportation costs in spite of carrying heavy payloads. The gasoline powered engines are quiet and easier to start and their working is known by most operators. The engine provides excellent fuel efficiency though the initial costs of buying an engine are high.      

In case you want to use the trucks for carrying heavy equipment, then the C6500/C7500 and the C8500 should be a better option. These trucks are known as the heavy haulers in the GMC lineup. Latest models such as the C8500 have a GVWR up to 27,660 kgs. These Topkick models have an automatic transmission system which proves to be a great help for drivers who are not experienced. Also the automatic transmission system helps in efficient consumption of fuel. The torque converter also helps to maximize the power output of the engine and also helps to prevent shock loading that can result on increasing the life of the drivetrain component. The transmission temperature gauge can prevent the vehicle from overheating.      

General Motors offers a warranty of two years on any of the Topkick Models for unlimited kilometer use in that two year period. Warranty is extended to five years for components like frame rail, cross members and sheet metal rust. The 6.6L Duramax diesel engine has a warranty of 5 years or 1,60,000 kms, whichever is less. The 7.8L Duramax diesel engine has a warranty of 3 years for unlimited kms during that period.