Advances in Additive Technology for Limited Slip Axles – Part I Friction Test Development

Limited slip differentials have been used for many years in the automotive industry to improve driving control and reduce chatter and vibrations from the rear axle. The choice of proper lubricant is essential to quiet and smooth operation. Special additives are available to modify the frictional response in the coupling to eliminate stick-slip problems. In recent years, there has been a trend in the US toward higher axle sump temperatures. Therefore, new limited slip additives are needed with better thermal stability and frictional performance. In this paper, we will present the results of the development of a bench test to measure the friction performance of limited slip lubricants.