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This work aims to summarize in a single form all legal requirements that dictates the minimum safety compliance required by government edicts to any wheel manufacture to have their products available for passenger or light truck vehicle in any country around the world in the year of 2016. It is not intention of this paper compare or discuss the different requirement among the countries but indicate to the manufactures of wheels what legal edicts they need to meet in case they are willing to go overseas to explore the wheel market of other country. Before start designing wheels for passenger or light truck application, any manufacture should be sure about what the government of the new market demands for wheels when installed on vehicle axis or just available as temporary spare. Another objective of this paper is to be a short reference for new automakers to know what to demand from their suppliers of wheels before starting business with them or shipping vehicles to any new market.

This paper will focus whining noise on rear axles applied in mid-size trucks. Vehicle integration changes during development affect directly the gear noise perception, in which it may be intensified. Also, gear material and heat treatment choices for the rear axle need to be done carefully, taking into consideration the integration changes and also the driver usage. A lessons learned collection over the diverse aspects of a rear axle whining noise will be the basis of this paper.

Vehicle Fuel Economy and Emission measurements requires road load determination by standardized Coast-down test. Worldwide stablished standards for testing and calculation apply second order polynomial fit models to describe road load. The common approach on road load analysis and validation is by direct comparison of coefficients and corresponding parabolas. This paper discuss an alternative approach (currently used by the USA Environmental Protection Agency) for estimating road load energy loss on standard test driving profile. Combining simple physical concepts on Work with the road load model and the chassis dynamometer driving profile, equations are derived describing the energy loss as a function of road load coefficients on a fuel economy test.

Basic driveline configurations offered in mid-size trucks have a standard “open” differential. Open differentials allow smooth cornering, as the outside tire must spin faster on corners as it travels a larger arc, when compared to the inner tire. This system has a main problem when traction is lost, due to slippery roads, different friction coefficients between pavements or even when the axle is submitted to a twist ditch. All of the power goes to the wheel with the least traction and the pickup is stuck. In order to improve traction on these situations, limited slip differentials were developed. A limited-slip differential will prevent excessive power from being allocated just to one wheel, and thereby keeping both wheels in powered rotation. There are several solutions offered in the market, each one presenting different torque transfer capabilities.

The new Brazilian program Inovar Auto coming in 2017 has raised the level of efficiency awareness from vehicle fuel economy in km/L to energy consumption in MJ/km. In this scenario, automakers are implementing several vehicle optimization strategies and new technologies to meet vehicle energy efficiency targets and consequently reduce fuel consumption and exhaust gases emissions. One of these technologies is the START-STOP system that basically turns the engine off when the vehicle is at idle and after some safety and operating trigger conditions are met. A new concept has been developed to evaluate an internal combustion engine start efficiency considering both the electric energy provided by starter motor and the fuel chemical energy required to start and sustain combustion. This concept of start efficiency is of particular interest for Flex Fuel engine where there is a high difference in energy content level between commercial gasohol (E27) and hydrous ethanol (E100) fuels.

The Brazilian automotive market presents special characteristics: at the same time that it demands similar technologies applied in developed markets like USA and Europe for luxury cars, in the sub-compact entry-level segments (a segment where the profit margin is very tight) there are unique characteristics that justify the development of different cars. Taking into consideration the mini cars segment, there is no car developed specifically for the Brazilian market. While the mini cars development for the entry level segment is still rare, every new auto show presents new proposals and some of them are on the streets, but most are mainly focused in the luxury segment. These vehicles currently in the market are in a price range where it is not economically feasible for them to be acquired by someone who is coming from a motorcycle-based usage.

Changes in the macro economic scenario of Brazil during the latest 10 years resulted on several changes in the auto industry market. One, which affected important requirements of the light duty trucks, regards the migration of customers from passenger car segments to light duty pickups. A considerable portion of these new pick-up customers expects an overall level of comfort, handling, noise and vibration similar to the levels found in passenger cars. One possible conclusion of this trend is that an optimized vehicle system integration is vital to prevent potential issues and to assure the achievement of customer satisfaction. Among several vehicle systems, the Drivetrain integration deserves the major attention. This paper shares lessons learned on the integration of the manual Transmission, external shifter, mountings, propeller shaft, rear axle and suspension with the rest of the vehicle.