Patent ID: 8042609
Filing Date: 2011-10-25
Classification: F16H

Abstract:
1. A method for improving the fuel economy of a vehicle comprising: providing an engine coolant to absorb heat from an engine; providing a heat exchanger in fluid communication with the engine coolant, the heat exchanger being at least partially submerged in a transmission fluid within a transmission sump; and transferring the engine coolant through the heat exchanger such that heat from the engine coolant is absorbed by the transmission fluid until the transmission fluid reaches a first predefined temperature, wherein a viscosity of the transmission fluid is decreased thereby reducing spin losses and improving fuel economy; blocking and preventing, via a valve, the transfer of the engine coolant to the heat exchanger after the transmission oil reaches the first predefined temperature, wherein the heat exchanger is disposed inside the transmission and is configured to transfer heat energy between the engine coolant and the transmission oil; and unblocking, via the valve, the transfer of the engine coolant to the heat exchanger when the transmission fluid reaches a second predefined temperature that exceeds the first predefined temperature and the temperature of the engine coolant.