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This paper describes the application of the Design for Manufacture and Assembly (DFMA) method at Chrysler. Attention is focused on the development of the clutch and brake pedal and bracketry system of the PL project in the Small Car Platform. The Chrysler DFMA procedure including competitive evaluation and value engineering was utilized during the initial design phase involving product concept development from the original functional and manufacturing requirements. After the first laboratory tests, a number of key design and manufacturing concerns surfaced and led to a second cycle of DFMA analysis. The procedure permits major design functions and manufacturing and assembly process issues and criteria to be incorporated in the initial design stages.

Higher horsepower per liter engines have put more demand on the crankshaft, often requiring the use of forged steel. This paper examines cost reduction opportunities to offset the penalties associated with forged steel, with raw material and machinability being the primary factors evaluated. A cost model for crankshaft processing is utilized in this paper as a design tool to select the lowest cost material grade. This model is supported by fatigue and machinability data for various steel grades. Materials considered are medium carbon, low alloy, and microalloy steels; the effects of sulfur as a machining enhancer is also studied.

The automobile industry has been using high-density polyethylene (HDPE) as a material to fabricate fuel tanks. Because untreated HDPE is permeable to the primary constituents of gasoline, these fuel tanks are now being produced with various barrier technologies that significantly reduce this permeation rate. Four currently available barrier technologies are fluorination, sulfonation, coextrusion, and the laminar barrier technology. These technologies have successfully proven to decrease the permeation rate of pure gasoline. However, it is suspected that their effectiveness may be reduced when alcohols are introduced into the fuel blend. In this work, we determine the permeation rates of gasoline-alcohol fuel blends through HDPE by conducting tests on 22-gallon HDPE fuel tanks and on small HDPE bottles fabricated with and without these barrier technologies. The goal of this study is to provide a comprehensive evaluation of these four barrier technologies.

A unique opportunity arose to make a direct comparison of aluminum, sheet molding compound (SMC) and steel using a common hood design. In considering all possible material combinations of inner and outer panels, it was discovered that some of the combinations were incompatible due to material properties. Only the compatible material combinations were considered. Three different joining techniques - welding, bonding and bonded hem flanging - were evaluated. The cost, weight and structural performance of the chosen hood material combinations were established. Areas of further development were identified, including design optimization for specific material combinations.

A running loss test procedure has been developed which integrates a point-source collection method to measure fuel evaporative running loss from vehicles during their operation on the chassis dynamometer. The point-source method is part of a complete running loss test procedure which employs the combination of site-specific collection devices on the vehicle, and a sampling pump with sampling lines. Fugitive fuel vapor is drawn into these collectors which have been matched to characteristics of the vehicle and the test cell. The composite vapor sample is routed to a collection bag through an adaptation of the ordinary constant volume dilution system typically used for vehicle exhaust gas sampling. Analysis of the contents of such bags provides an accurate measure of the mass and species of running loss collected during each of three LA-4* driving cycles. Other running loss sampling methods were considered by the Auto-Oil Air Quality Improvement Research Program (AQIRP or Program).

An OEM Natural Gas Vehicle (NGV) has been developed to address recently enacted Clean-Fuel Vehicle legislation. The NGV incorporates advanced fuel storage and fuel metering technologies to produce very low emissions and to provide superior customer value compared to aftermarket conversion units.

This study analyzes the vibration characteristics of the valve train of a 2.0L SOHC Chrysler Corp. Neon engine over a range of operating speeds to investigate and demonstrate the advantages and limitations of various dynamic measurements such as displacement, velocity, and acceleration in this application. The valve train was tested in a motoring fixture at speeds of 500 to 3500 camshaft rpm. The advantages of analyzing both time and frequency domain measurements are described. Both frequency and order analysis were done on the data. The theoretical order spectra of cam displacement and acceleration were computed and compared to the experimental data. Deconvolution was used to uncover characteristic frequencies of vibration in the system. The theoretical cam acceleration spectrum was deconvolved from measured acceleration spectra to reveal the frequency response function of the follower system.

A selection of commercially available chromium and chromium-free post phosphate rinses along with a deionized water rinse were evaluated over several zinc and zinc-alloy coated sheet steels. The test specimens were pretreated and electrocoated on-line in an automotive assembly plant. The effect of the rinse treatments on the cosmetic corrosion performance of the substrates, after 5 years of exposure in an outdoor scab corrosion test was determined. After this exposure none of the rinse treatments had performed better than deionized water rinse on zinc and zinc-iron coated sheet. The zinc-nickel coating showed improved scribe creepage when treated with the Cr+6/Cr+3 rinse. Data is provided comparing the concentration of the treatments used vs scribe creepage and chipping corrosion paint loss.

A comprehensive selection of automotive sheet steels were exposed in an outdoor scab corrosion test to provide a base-line of cosmetic corrosion performance. Eighteen different coated sheet steels along with CRS as a control were processed using two commercially available zinc phosphate chemistries. The phosphating was done using both immersion and spray phosphate processes in a laboratory and an automotive assembly plant. Scribe creepage results are reported for 5 years outdoor scab exposure. Comparisons of the scribe creepage behavior of CRS, zinc, and zinc alloy coatings and the effect of the phosphate treatment are provided. An estimate of 10 years field performance is made.

Natural gas-fueled vehicles impose unique requirements on exhaust aftertreatment systems. Methane conversion, which is very difficult for conventional automotive catalysts, may be required, depending on future regulatory directions. Three-way converter operating windows for simultaneous conversion of HC, CO, and NOx are considerably more narrow with gas engine exhaust. While several studies have demonstrated acceptable fresh converter performance, aged performance remains a concern. This paper presents the results of a durability study of eight catalytic converters specifically developed for natural gas engines. The converters were aged for 300 hours on a natural gas-fueled 7.0L Chevrolet engine operated at net stoichiometry. Catalyst performance was evaluated using both air/fuel traverse engine tests and FTP vehicle tests. Durability cycle severity and a comparison of results for engine and vehicle tests are discussed.

Typical sand-casting techniques have been shown to be inappropriate in pouring particulate reinforced aluminum metal matrix composite (Al-MMC) castings. New gating/risering configurations were necessary to produce castings of acceptable soundness. Several automotive components, including brake rotors, cylinder liners and camshaft thrust plates, were prepared using special techniques. Initial durability test results of several Al-MMC prototype components are presented.

There are important changes unfolding in domestic industry. In the face of increased competition and the reality that traditional practices are no longer sufficient, manufacturers are taking daring new looks at the ways that they do business. Platforms and small business units are being formed within large companies to manage product lines. Cross-functional teams are replacing functional organizations as the driving forces in product development. Authority and leadership are being shifted lower and lower Into the working ranks, and the reengineering of work processes is becoming the challenge. This paper presents part of the story of Chrysler's Small Car Platform. It begins with an overview of the platform system. Then it focuses on the Process Phase of a vehicle program. The story is told to illustrate our experience in a continuous improvement process.

Resin transfer molding (RTM) is the process of choice for the Body Panels of the Viper Sports car. The objective of this paper is to outline the reasons for the choice of RTM, and discuss development of technology for Class A surfaces and the paint system. Accomplishments to date and finally the work yet to be completed will also be defined. Conclusions from the work to date indicate that the RTM process enables a reduction in vehicle development time through faster prototypes and tool build times and that high quality, Class A surfaces can be successfully achieved even with epoxy tools. Additional work is ongoing to reduce cycle times and finishing costs, and to improve the in-process dimensional stability.

To evaluate and refine interior architecture of the new Dodge Ram pickup truck three years before production, a road worthy interior package validation buck was built using a fiberglass body shell. Molds for the shell were made using CAD/CAM techniques. Advanced CAD/CAM techniques were used to build the interior buck of a subsequent model from individual panels molded in carbon fiber. This buck also included inner structural panels and interior trim components taken from CAD data. For this and subsequent new vehicle programs, refinement of construction techniques allows the bucks to serve as aids in product design and manufacturing feasibility studies.

Chrysler Corporation has developed an 8.0-liter engine for light truck applications. Numerous features combine to produce the highest power and torque ratings of any gasoline-fueled light truck engine currently available while also providing commensurate durability. These features include: a deep-skirt ten-cylinder 90° “V” block, a Helmholtz resonator intake manifold that enhances both low and mid-range torque, light die cast all-aluminum pistons for low vibration, a unique firing order for smooth operation, a “Y” block configuration for strength and durability, a heavy duty truck-type thermostat to control warm up, and a direct ignition system.

Chrysler Corporation's Jeep and Truck platform implemented a new design and prototype process for the body-in -white of a new pickup truck. A team approach achieved concurrent body design, stamping die design, assembly process development, and assembly tooling development. The first domestic US industry use of a 100% electronic design and release system was instrumental in the process. The new process produced a prototype body-in-white on time at 95 WBVP (weeks before volume production) with the highest level of production-intent components ever achieved within Chrysler at this stage of development.

A new 3.5 liter, 60 degrees V6 engine has been designed specifically for Chrysler's 1993 MY line of mid-size sedans - Dodge Intrepid, Eagle Vision, Chrysler Concorde and New Yorker. This new engine features many new components for enchanced performance. The cylinder head has a single overhead cam, four valve-per - cylinder design. The intake system is a cross-flow design equipped with dual throttle bodies, and the manifold also incorporates a vacuum operated tuning valve that increases the mid-range torque of the engine. A windage tray is used on every engine to reduce drag on the rotating components within the crankcase. Dual knock sensors (one per cylinder bank) are used to take advantage of the aggressive spark advance and high compression ratio. The engine also utilizes a plastic, helical, water pump impeller that contributes to low parasitic power losses. The engine incorporates many components and features to ensure durability.

Most United States vehicle assembly plants produce significantly more automatic transmission equipped vehicles than manual transmission vehicles. Assembling these two vehicles on a common production line can create complexity problems. This paper describes the design and development of a pre-assembled manual transmission clutch and flywheel modular assembly which reduces most of these problems. This assembly is used on the 1993 model year mini-van with a 2.5L four cylinder engine. This modular clutch system utilizes the same starter ring gear carrier (driveplate) used on automatic transmission equipped vehicles. It pilots into the crankshaft similar to the automatic transmission torque converter. It is balanced as an assembly which results in a lower system imbalance. A significant system piece cost saving, in comparison with today's competitive market, was achieved.

Most of the current fuel supply specifications, including the key parameters in the transient fuel control strategies, are experimentally determined since the complexity of multiphase fuel flow behavior inside the intake manifold is still not quantitatively understood. Optimizing these specifications, especially the parameters in transient fueling systems, is a key issue in improving fuel efficiency and reducing exhaust emissions. In this paper, a model of fuel spray, wall-film flow and wall-film vaporization has been developed to gain a better understanding of the multiphase fuel-flow behavior within the intake manifold which may help to determine the fuel supply specifications in a multi-point injection system.

Chrysler Corporation Interior Electrical\Entertainment Department currently has three different mounting tab configurations on the radio escutcheon required by five platforms for radio installation. Prior to the re-organization into platforms, the corporation had one corporate mounting configuration. The reorganization into platforms encouraged diversification including different radio mounting locations. This however, requires three separate part numbers for the same radio unit, resulting in additional cost. How can we assure product diversification between platforms while controlling cost and managing complexity?