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As a result of the introduction of the modern tilt cab, suspension designs are required to be more sophistocated in order to provide the ride quality expected from a modern truck. The purpose of the study undertaken was to determine practical methods and the respective considerations and decisions required to mount a cab to various chassis constructions. The basis of this exercise was a European type truck of cab over configuration. Various stages in the concept are highlighted in addition to relative decisions and required considerations. Because measurable standards exist on ride quality, this aspect was studied briefly due to the fact that generally required comfort standards vary a great deal between countries. The final objective was to determine the cab structural damage incurred through the cab suspension, and to determine projected vehicle mileages on various highways before structural damage is caused.

This paper outlines the reasons for the design of a heavy duty truck having a sophisticated cab suspension system, to cater for the special conditions of transeuropean operation. It describes the design and development of the Ford Transcontinental cab suspension, and the resulting ride performance. The unique cab tilt system used in conjunction with the cab suspension is also described.

Instrumented and subjective cab ride quality data is obtained for a COE tractor/trailer combination in which two different cab isolation systems were installed. In the first system, the rear of the cab is suspended on soft springs while the front is pinned to the frame, allowing cab pitch only. In the second system, the rear of the cab is pinned to the frame while the front is suspended on soft springs. The relative performance of these two systems is compared. Results are compared with predictions of a multi degree of freedom tractor/trailer computer model.

This paper discusses the application of seals to tapered roller bearings and is intended as a guide to (1) the engineer designing a sealed application, (2) the production personnel installing seals in the application and (3) the maintenance personnel servicing the application. The paper is deliberately not referenced so that when problems are encountered that cannot be solved by using this guide, the bearing or seal manufacturer is consulted.

Elastomeric radial lip seals are designed to retain lubricants and exclude contaminants. Dual lip designs have evolved to achieve these goals. A study was conducted to determine the effectiveness of a given dual lip design. Comparisons were made to a single lip design. Under the given test conditions, the single lip design outperformed the dual lip design.

This paper discusses the technique and problems associated with in-plant and body shop repair of aluminum auto body sheet. Metallic and nonmetallic repair procedures are discussed for in-plant repair of aluminum auto body sheet. An after-market procedure for repair of aluminum sheet is also presented, as well as a new procedure for arc welding of thin gauge aluminum sheet for in-plant and after-market repair.

A fractional factorial experimental study was conducted to determine the effect of seal size on seal design. The seven factors studied were inside lip diameter (w/o spring), seal size, shaft-to-bore offset, spring position, contact width, flex section thickness, and material modulus. The fractional factorial experiment was designed so all interactions involving seal size were determinable. Leakage was measured as the response or dependent variable. The large seal (nominal 100 mm) differed from the small seal (nominal 50 mm) in three areas: (1) shaft-to-bore offset was not tolerated by the large seal, (2) the spring position was required to be closer to the contact line with the large seal, and (3) a higher material modulus was necessary with the larger seal.

For purpose of clarifying the effect of quantity of lubricating oil supplied to the seal lip portion on sealing characteristics of oil seals, relations between the typical constructional applications of the fitting portion for oil seals and the quantity of the lubricating oil supplied to the oil seals are discussed. Then the necessary minimum quantity of the lubricating oil for preventing the seal lip from wear is investigated. And it is clarified that the decrease in sealing characteristics occurs when the lubricating oil is supplied insufficiently to the seal lip portion and, finally, the countermeasure is discussed.

Ethylene/acrylic elastomers are new candidate materials for challenging automotive sealing problem areas. They promise attractive blends of thermal stability, oil and weather resistance, mechanical properties and low temperature performance for service formerly restricted to the more expensive high temperature silicone and fluorocarbon elastomers. Our preliminary research and development on specific automotive sealing applications has produced data that enables us to position ethylene/acrylic elastomers in relationship with the other commercial seal materials. Revealed are the results of our chemical, material and ongoing field testing programs which are helping us predict the future of ethylene/acrylic elastomers as viable solutions to critical sealing problems.

A new SAE Recommended Practice for automotive water pump seals has been proposed through committee work. The existing standards, specifications and other publications have been reviewed to find practical information on the design and use of water pump face seals. The paper presents the committee's recommendations on types of seals and materials, design data, and qualification and inspection information. The paper also describes test methods, equipment and system orientations for evaluating seal performance.

Guidelines for forming aluminum auto body panels have been developed for use by part and forming tool designers. Full size proof die and production die tryout programs were conducted to establish part design details plus forming tool and process parameters. Typical panel applications for four aluminum auto body sheet alloys are discussed.

A new tooling technique has been developed to fabricate substantially longer split free collars than were previously possible in aluminum body sheet alloy. This technique is economical and can often be incorporated into existing tooling. The new process has application in the manufacture of heat exchanger, auto body sheet, and bumper reinforcement products.

This paper describes a continuing research program on traffic noise annoyance that is being conducted by the Societal Analysis Department at the General Motors Research Laboratories. The work involves a combination of laboratory, field and computer modeling studies. Results are intended to provide a better fundamental understanding of noise-induced annoyance. Potential applications include the evaluation of various vehicle noise reduction programs.

A tensile strip test has been developed for evaluating friction under conditions which simulate the stretching of sheet over the punch corner radius in forming a shallow stamping in a typical draw die. Preliminary results are presented for the aluminum alloys 5182-0, 2036-T4, 6009-T4 and 6010-T4,which are used for automotive applications. Tests were conducted with various lubrication conditions, different corner radii and with prestrained sheet. For given friction conditions, the maximum strain obtained over the face of the punch was significantly affected by small amounts of prestrain or small changes in the tensile/yield ratio of the sheet.

Fatigue tests have been conducted to evaluate several methods of joining aluminum sheet for automotive applications: resistance spot welds; GMA spot welds; fillet welds; rivets; mechanical clinching; bonding; and, combinations of bonding with spot welding, riveting, and clinching. Spot welded, riveted or clinched lap joints in 1.0 mm (0.040 in.) aluminum have fatigue strengths 1/2 to 2/3 those of spot welded joints in 0.8 mm (0.032 in.) steel. Bonding in combination with these joining techniques produces joints having fatigue strengths equal to or higher than those of spot welded steel joints. Simulated service exposures generally reduce long-life fatigue strength of combination joints.

The dent resistance of aluminum and steel autobody panels has been studied under controlled laboratory conditions and by field observations and measurements of actual hailstone damage. Analysis of the results shows that very nearly the same response occurred in the lighter weight aluminum components as occurred in the steel panels. The autobody components were all 1977 model year production panels. Laboratory testing included four steel and four aluminum hoods, both painted and unpainted. The hailstone damaged components included a steel hood, aluminum doors and an aluminum fender. The aluminum and steel panels were damaged in the same hailstorm during May 1977. The analysis of denting resistance presented in this paper is based on insight and experience gained from a four-year cooperative program of Reynolds Research and several automobile companies.

A test has been devised by which lubricants for sheet metal forming may be assessed for their lubrication capability and their effect on galling. An apparatus was constructed which simulates drawbeads, a mechanism which controls sheet metal flow into a die. The load to draw sheet metal through the simulated drawbeads varies for different lubricants. Comparison to the load for a standard lubricant gives a lubricity rating. Lubricants are also rated for their effect on galling. The lubricity rating obtained by this laboratory method correlates with the performance of the lubricants in production runs.

The interest in aluminum alloys and aluminum joining in the automotive industry has increased considerably over the past few years as a result of new fuel economy, air pollution and safety requirements. Aluminum is the best alternative to steel to make lighter and more fuel-efficient automobiles. Several aluminum alloys have been considered for body sheet components. The new Alcoa 6009-T4 and 6010-T4 alloys were developed and introduced in 1976 to increase the attractiveness of aluminum for body sheet components. These alloys have good formability in the as-received condition and superior strength and dent resistance in the aged (-T6) condition which can be achieved in paint bake cycles. These alloys are similar in composition and do not require scrap segregation. In addition, the 6009/6010 alloys provide improved welding characteristics through a combination of better metallurgical characteristics and lower and more uniform surface resistance.

The need for motor vehicle noise regulation is briefly reviewed and the provisions of current Canadian federal standards are outlined. An assessment of the effectiveness of current regulations is made in general terms and possible future regulatory actions are discussed. The need for co-ordination of federal regulation of the new vehicle and provincial or municipal regulation of the vehicle in use is emphasized with particular reference to the importance of voluntary standardization in the current situation in Canada.

The preparation of objective legislation to control noise from motor vehicles is well advanced in Australia and enforcement has commenced in some Australian States. A design rule setting criteria for noise emissions from new vehicles was published by the Federal Department of Transport in 1972 and a revised design rule reducing the maximum permissible levels was finalized in 1976 but its implementation has been deferred. Following extensive surveys, regulations setting criteria for in-service vehicles have been prepared by the Environment Protection Authority in Victoria and it is anticipated that these criteria will be adopted by all States in Australia.