A. Engines that start and stop frequently tend to have several potential lubrication related issues. One is that if the engine is started in cold weather conditions, most of the engine wear can occur at start up so proper viscosity is critical to start up lubrication. As a side not, heavy duty 15W-40 engine oils may only provide adequate start up lubrication down to +15F whereas SAE 10W-30, 5W-30 or 5W-40 grades can far exceed that lower limit reducing the higher wear than can occur under these cold temperature conditions. Secondly, engines that start and stop frequently may incur condensation which can contaminate the oil causing loss of anti-corrosion properties and start and stop operation also cause fuel dilution due to improper fuel combustion by not bringing the engine up to operating temperature.