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Splash and spray conditions created by tractor-trailer combinations operating on the Federal highway system have been studied and tested for many years with mixed results. Past events are reviewed briefly in this paper. In additional testing during 1983, using new state-of- the-art splash/spray suppressant devices, some encouragement was provided that these devices could work. The 1984 Motor Vehicle Manufacturers Association (MVMA) test program was designed to develop practicable and reliable test procedures to measure effectiveness of splash and spray reduction methods applied to tractor-trailer combination vehicles. Over 40 different combinations of splash/spray suppression devices on five different tractors and three van trailer types were tested. The spray-cloud densities for some 400 test runs were measured by laser transmissometers and also recorded by still photography, motion pictures, and videotape. On-site observers made subjective ratings of spray density.

This article is a new methodology to create a strong and reliable procedure to measure oil level at dealers. Most of time, commercial trucks run full loaded. Engine oil level indication systems are designed to measure oil level at that condition. However commercial trucks are assembled and sold empty and without bodies for trucks. In result of this condition, vehicles with a false indication of low engine oil level are detected at dealers' pre-delivery inspection, resulting in oil addition. This oil addition causes unnecessary costs, since vehicles are produced with maximum oil level. The methodology presented in this study analyzes and treats all variables involved in engine oil level measurements from engine production line until dealers' pre-delivery inspection

During the development of a new friction material, besides the interface between lining/drum is also fundamental take in account all aspects involving the attachment of the linings on the brake shoes. This paper presents an optimization approach to the development and manufacturing parameters of brake linings, applied on medium and heavy duty commercial vehicles, aiming to assure the correct specification of the riveted joint clamp forces. These evaluations were conducted based on the quality tools documents and the theoretical aspects of the product usage as well as the modeling of key elements of the referred mechanism throughout various known applications. A calculation methodology was developed based on brake geometry, its generated forces and braking reactions required for each vehicle family.

The automotive industry has been increasingly researching and working on improving vehicle and passenger safety over the years. Following countries such as the United States and European Union, the Brazilian government has been publishing many resolutions with the objective of improving the safety of their fleet. With the publication of resolution 312 from CONTRAN (National Traffic Counsel), on April 3rd, 2009, the installation of ABS (Anti-lock Brake System) feature has become mandatory for all car and truck models to be sold in Brazil, following a staggered implementation starting on January 1st, 2010. The ABS system adds to the vehicle's current brake system, not allowing the wheels to lock during braking, which helps preserve the vehicle's stability and improve its safety, thus avoiding accidents. The technology, which is already available in a few car models, is not yet developed for the heavy trucks applications in this market.

A number of service fatigue history summarization statistics are examined for their suitability in regenerating the history in the laboratory. Evaluation criteria applied include: fatigue damage-per-level equivalence, implementation simplicity, waveform similarity, and fatigue life equivalence. The results suggest that a three-dimensional “From-To” matrix that includes sequence information about the original variable amplitude histories, is optimal for service history reconstruction.

A straight cut tailpipe tip was empirically evaluated for the effect that the tip's orientation to a cross-wind had on the ability to reduce exhaust system backpressures associated with the purging of the combustion products. The straight across tip was attached to a vehicle at various angles of inclination to their axes while exhaust back pressure and performance readings were recorded. Testing indicated that there is a preferred orientation to reduce backpressure. Attempts to match on-vehicle data with wind tunnel data were met with partial success.

One of the difficulties in predicting the structural behavior of vehicles such as the full size pickup trucks is the non-linearities involved during the course of the durability events. The current practice in durability and fatigue life prediction of vehicles is to conduct fatigue analysis on the structure using the measured road loads and estimate the fatigue incurred using the in-house and commercially available programs. In this paper the authors attempt to seek a different solution to the durability problem by conducting an upfront non-linear analysis. The results are then compared with the prediction by the fatigue life program in addition to the durability test results obtained on the early prototypes. To conduct the non-linear analysis ABAQUS FEA program is chosen for this investigation and for the linear analysis MSC/NASTRAN is utilized. Subsequently in-house fatigue program is used to predict the fatigue incurred.

The use of a corrosion inhibited arsenical brass alloy for copper/brass radiator tubes has been identified as an effective means to protect the radiator tubes from external dezincification attack, which is generally caused by an exposure to excessive road salts in the regions such as Montreal and Toronto in Canada. Laboratory test methods, their results and field data verifying improved radiator life are presented.

This paper presents the experience of Ford Motor Company and Hitachi Metals Ltd., in the development and design of the exhaust manifolds for the new 1997 Ford 6.8L, Vl0 gasoline truck engine. Due to the high-exhaust temperature 1000 °C (1832 °F), heat-resisting nodular graphite irons, such as high-silicon molybdenum iron and austenitic iron with nickel cannot meet the durability requirements, mainly thermal fatigue evaluation. The joint effort by both companies include initial manifold design, prototype development, engine simulation bench testing, failure analysis, material selections (ferritic or austenitic cast steel), production processes (casting, machining) and final inspection. This experience can well be applied to the design and development of new cast stainless-steel exhaust manifolds in the future. This is valid due to the fact that US EPA is requiring all car manufacturers to meet the new Bag 6-Emission Standards which will result in increased exhaust gas temperature.

A tunable stamped collector was developed to improve vehicle performance, drive-by noise and subjective noise quality, and reduced thermal stress concentrations. The stamped collector is located at the junction of the legs of the down pipe/catalytic converter assembly for a transverse mounted V-6 engine and acts to equalize the leg length of the down pipe, as well as provide acoustic tuning volume. This collector differs from most other methods to equalize leg lengths on transverse mounted engines in that it has a tuning chamber incorporated into the design itself, which allows for specific noise frequencies to be reduced. Performance characteristics were measured for a conventional down-pipe and the stamped collector using the following analysis techniques: Frequency analysis of tailpipe noise emissions. Drive-by noise emissions. Horsepower measurements using an engine dynamometer.

Downhill tests are widely used as a method of evaluation, development and validation of braking efficiency, friction pair durability, braking balance, as well as fade characteristics and recovery of friction material properties. This test procedure is used for both: passenger vehicles and light & heavy commercial vehicles. The energy levels in the brake system are higher on commercial vehicles and the thermal characteristics much more critical. Added to the fact that such tests are conducted on public highways, it has an intrinsic security risk for both the vehicle tested and all others around. Until a few years ago, it was still feasible to conduct tests downhill on different routes keeping a high security level. Given an increasing traffic on highways, where the test is currently carried out, a need to create a similar downhill procedure (called Guaporé Mountain Test) within a Proving Ground under controlled conditions has been noticed.

A comparison between ‘Quasi-Transient’ and Steady-State (SAE J1349) engine dynamometer horsepower test procedures was conducted to determine the degree of correlation between the two test methods. Measurements demonstrated that the peak horsepower and torque measured using both techniques was similar. This information is useful as a development tool, because the ‘Quasi-Transient’ procedure allows for data to be collected over the engine RPM range much faster then the Steady-State method, allowing for the accurate testing of more engine/exhaust configurations in a shorter amount of time.

Frequency domain testing has had limited use in the past for durability evaluations of automotive components. Recent advances and new perspectives now make it a viable option. Using frequency domain testing for components, test times can be greatly reduced, resulting in considerable savings of time, money, and resources. Quality can be built into the component, thus making real-time subsystem and full vehicle testing and development more meaningful. Time domain testing historically started with block cycle histogram tests. Improved capabilities of computers, controllers, math procedures, and algorithms have led to real time simulation in the laboratory. Real time simulation is a time domain technique for duplicating real world environments using computer controlled multi-axial load inputs. It contains all phase information as in the recorded proving ground data. However, normal equipment limitations prevent the operation at higher frequencies.

The demand for improved fuel economy in both cars and trucks has emphasized the need for lighter weight components. The application of high strength steel to wheels, both rim and disc, represents a significant opportunity for the automotive industry. This paper discusses the Ranger HSLA wheel program that achieved a 9.7 lbs. per vehicle weight savings relative to a plain carbon steel wheel of the same design. It describes the Ranger wheel specifications, the material selection, the metallurgical considerations of applying HSLA to wheels, and HSLA arc and flash butt welding. The Ranger wheel design and the development of the manufacturing process is discussed, including design modifications to accommodate the lighter gage. The results demonstrate that wheels can be successfully manufactured from low sulfur 60XK HSLA steel in a conventional high volume process (stamped disc and rolled rim) to meet all wheel performance requirements and achieve a significant weight reduction.