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Several number of ball joints are used in the suspension system. For these ball joints, rubber dust covers are used in order to maintain sufficient lubrication and protect the ball joint from contaminants such as water and dusts. In recent years, the number of breakage or grease leakage of the dust cover used under ultralow temperature is increasing with the growth of automobile selling in developing countries. In this research, we have studied the mechanism of dust cover breakage under ultralow temperature by focusing on the low temperature behavior of a rubber material.

Lubricants such as wax and grease are used to improve adhesion, frictional properties, and sliding noise of thermoplastic elastomer (hereafter referred to as TPE) products used for automotive parts. These lubricants help improve the lubrication of products when added to TPE products or applied directly to the surface. Long-term effectiveness can be expected from the former method due to the gradual movement of the lubricant from the inside to the surface. Clarifying this transfer phenomenon should therefore be very important for predicting and controlling product characteristics. This paper reports on an analysis method applying infrared spectroscopy developed by the authors, and investigations conducted on the surface transfer of lubricants such as wax and grease for polyester TPE used for CVJ boots.

Hydraulic fluid (HF) specifications for mobile construction equipment called JCMAS HK and HKB have been established by the Fuels and Lubricants Committee of Japan Construction Mechanization Association (JCMA). The specifications are designated by two viscosity categories of single grade and multigrade. Each category has ISO viscosity grade (VG) 32 and 46. The JCMAS HK oils are recommended for use in hydraulic systems designed at pressure up to 34.3MPa(5000psi) and to heat hydraulic fluid up to 100 °C. These oils also provide wear control, friction performance, oxidation and rust protection, seal swell control and filterability performance. Two piston pump test procedures were developed to evaluate lubricating performance of these oils under high pressure conditions. The JACMAS HKB oils are classified as environmentally friendly oils due to the additional requirement for biodegradability.

In this study, a green process was developed to synthesize a novel molybdenum disulfide (MoS₂)-based friction modifier (FM) for improving fuel economy performance of lubricants. These new materials were synthesized using less hazardous elemental sulfur as opposed to other sulfur sources like hydrogen sulfide (H₂S) and carbon disulfide (CS₂). Using various bench and motoring friction torque tests, it was shown that friction reduction was benefited by utilizing low molecular weight organic backbone when designing molybdenum FMs. Also, it was shown that newly synthesized molybdenum-based FMs were comparable to other well-known MoS₂ precursors.

Technical impacts on engine oil performance by the use of waste cooking oil as bio-diesel fuel (BDF) are not well understood while the industry has made significant progress in studies on quality specifications and infrastructure. The authors, who consist of a consortium organized by Japan Lubricating Oil Society (JALOS), examined technical effects of waste cooking oil as BDF on engine oil performance such as wear and high temperature corrosion using vehicle fleets and bench tests to identify technical issues of engine oil meeting the use of BDF. The study brings fundamental information about technical impacts of BDF on engine oils.

Since construction machinery manufacturers recommend various brands and types of greases for their machinery, customers would benefit from a standardized grease which can be used in all construction machinery. Furthermore, construction machinery manufacturers have many experiences of field problems caused by commercially available and commonly used EP Lithium greases. Therefore, the Fuels and Lubricants Committee of Japan Construction Mechanization Association (JCMA) has developed a new grease specification called “Japan Construction Mechanization Association Specification (JCMAS) GK,” for construction equipment. The JCMAS GK includes requirements for National Lubrication and Grease Institute (NLGI) No. 1 and No. 2 consistency grades. The JCMAS GK greases have enough lubricating properties for periodical grease fitting of most construction machines, hydraulic excavators, bulldozers and wheel loaders. The JCMAS GK greases are applicable from -20 to +130 degrees Celsius.

This paper describes that the effect of surface texture of sealing lip on lubrication and sealing performance examined experimentally on practical aspect. Hub seals of PAC type were used in this study. A test apparatus and operating procedure were shown. The seal which had texture on the lip had lower frictional torque than plain one. The effect of friction reduction with the textured surface preserved up to 15 cycles, which was equivalent to a travel distance of 30,000 km. The textured surface 10 μmRz with grease on the lip kept sealing performance up to -0.10 MPa in static and dynamic conditions. The endurance time of sealing of the textured surface was almost the same as that of the plain surface in seal endurance test with muddy water.

The heightened interest level in Fuel Economy for Heavy Duty Diesel Engines the industry has seen over the last few years continues to be high, and is not likely to change. Lowering the fuel consumption of all internal combustion engines remains a priority for years to come, driven by economic, legislative, and environmental reasons. While it is generally assumed that lower viscosity grade lubricants offer fuel economy benefits, there is a lot of confusion about exactly what drives the fuel economy benefits. Fuel Economy claims in trade literature vary over a broad range and it is difficult for the end user to determine what to expect when a change in lubricant viscosity is adopted for a fleet of vehicles in a certain type of operation. This publication makes an attempt at clarifying a number of these uncertainties with the help of additional engine test data, and more extensive data analysis.