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New methods are required for implementing the proliferation and sophistication of electronic controls and features to meet the customer's quality expectations. Vehicle electronic integration provides a potential solution for reconciling the seemingly contradictory objectives of high quality at reasonable cost. No module can be considered independently with this global approach. OEM subsystem and component suppliers' devices will need to play in concert with the overall vehicle's electrical/electronic strategy. Some new, separately packaged electronic features may eventually be assimilated within the framework of other electronic controllers.

A method is proposed to qualify automotive component designs in the laboratory using multiaxial real time load/strain input data acquired in the field. Fatigue damage analysis methods are used to edit the field data to produce an accelerated test cycle that retains all of the damaging real time load histories present in the original test cycle. Use of this procedure can contribute to a significant reduction in product design/development time.

Tapered roller bearings have proven successful in a number of high-volume automatic transaxle designs. Typically, tapered roller bearings are required to carry high loads generated by helical and hypoid gears. To meet the demands of a successful design, a number of factors must be considered in the selection and application of tapered roller bearings. This paper presents a discussion of these factors as well as results from Chrysler's transaxle testing. Selection of tapered roller bearings is based on the transmission duty cycle developed using load and speed histograms, gear data, size constraints, and life requirements. A bearing life analysis considering the total transaxle system is conducted using a sophisticated computer program. Various system effects are analyzed including the load/speed cycle, housing and shaft rigidity, lubrication, bearing setting, thermal effects, and bearing internal design.

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.

Seats play an important role in determining customer satisfaction and safety. They also represent three to five percent of the overall vehicle cost and weight. Therefore, automotive manufacturers are continuously seeking ways to improve the areas of comfort, safety, reliability, cost and weight within the seat system. The purpose of this paper is to review the development of an automotive front seat constructed of injection molded nylon frames and metal mechanisms. This development program was initiated for the purpose of reducing vehicle weight while increasing the reliability and safety of the front seats. This paper will review the material and process selection decision, a design overview, the performance criteria and the results of tests performed on the injection molded front seats.

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.

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.

Five heats of vanadium-microalloyed steel with carbon contents from 0.29% to 0.40% and sulfur contents from 0.031% to 0.110% were forged into automotive spindles and air cooled. Three of the steels were continuously cast whereas the other two were ingot cast. The forged spindles were subjected to microstructural analysis, mechanical property testing, full component testing and machinability testing. The microstructures of the five steels consisted of pearlite and ferrite which nucleated on prior austenite grain boundaries and predominantly on intragranularly dispersed sulfide inclusions of the resulfurized grades. Ultimate tensile strengths and room temperature Charpy V-notch impact toughness values were relatively insensitive to processing and compositional variations. The room temperature tensile and room-temperature impact properties ranged from 820 MPa to 1000 MPa (120 to 145 ksi) and from 13 Joules to 19 Joules (10 to 14 ft-lbs), respectively, for the various steels.

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.

Fastener failure due to hydrogen embrittlement is of significant concern in the automotive industry. These types of failures occur unexpectedly. They may be very costly to the automotive company and fastener supplier, not only monetarily, but also in terms of customer satisfaction and safety. This paper is an overview of a program which one automotive company initiated to minimize hydrogen embrittlement in fasteners. The objectives of the program were two-fold. One was to obtain a better understanding of the hydrogen embrittlement phenomena as it relates to automotive fastener materials and processes. The second and most important objective, was to eliminate hydrogen embrittlement failures in vehicles. Early program efforts concentrated on a review of fastener applications and corrosion protection systems to optimize coated fasteners for hydrogen embrittlement resistance.

Environmental costs are a delayed financial burden that result from product decisions made early in the product life cycle--early material choices may create regulatory and waste management costs that were not factored into the acquisition cost. This paper outlines a step-wise approach to determine decision points; environmental, health, safety and recycling (EHS&R) cost drivers that affect decisions; and sources of information required to conduct a Life Cycle Management (LCM) review. Additionally, how LCM fits into the larger concurrent engineering framework is illustrated with an electrocoat primer example. Upstream and downstream supply chain processes are reviewed, as well as organizational challenges that affect the decision process.

The object of this paper is to present an overview of the procedure leading to the selection of suspension system pivot points, show how to resolve terrain and maneuver loads at the tire contact patch to the vehicles' structure, illustrate the modeling technique used for stress analysis of suspension system components, and illustrate a few examples of suspension system models used to aid in the solution of ride and handling problems.

The paper outlines testing, development, and operation of the first production four-wheel slip control system for passenger cars in the United States. The Chrysler Corp. calls the system “Sure-Brake,” but it is more generally known as “anti-skid.” The first portion of the paper deals with considerations that led Chrysler into the Sure-Brake system, the philosophy behind the system, and a detailed explanation of its operation. The second portion deals with the development and testing of the system, leading to its release as an option on the 1971 Imperial. The testing program introduced a new dimension to brake engineering. Before the advent of wheel slip control systems, many thousands of brake tests were conducted but were always terminated at the point of skid. These tests were also conducted mainly on black top or concrete roads. For the first time, thousands of stops were made at maximum deceleration on every available surface.

Chrysler Corp. has introduced two new features on their 1970 steering columns: an energy absorbing steering wheel which appears on the Barracuda and Challenger models; and an antitheft steering column which is standard on all car-lines. This paper describes the two engineering programs.

A SIMPLE method of predicting truck performance in terms of grade ability at a given road speed, taking into consideration rolling resistance, air resistance, and chassis friction is presented here. A brief review of fundamental considerations is given first, then the method recommended for predicting vehicle ability at a selected speed, and finally a few words on the prediction of maximum possible road speed and selection of gear ratios. The basis of the solution is the determination and expression of vehicle resistances in terms of horsepower - that is, in terms of forces acting at a velocity. A convenient method of solving the grade problem at a given speed is by means of a tabular computation sheet, which is given, together with tables and charts. These assist in making the computation an easy one as well as giving the necessary data on vehicle resistances.