Transmission Valve Body Line Pressure Modification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The Daimler Chrysler 46RE and 47RE automatic transmissions face limitations in line pressure increase during fourth gear and torque converter clutch (TCC) engagement, which affects transmission cooling and TCC engagement, while the 48RE transmission offers improved performance but is scarce and expensive.
Innovation Solution
Modifying the transmission valve body by adding an external fluid passageway to exhaust cutback ports to the fluid reservoir, enhancing line pressure response and allowing TCC engagement in any gear, thereby approximating the performance of the 48RE transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If the 46RE or 47RE transmission valve body is used as-is, then the device complexity is low and parts are abundant, but the line pressure increase is insufficient affecting transmission cooling and TCC engagement
Solution Approach 1:
The valve body modification is segmented into discrete components: drilling separate holes in the valve body, creating separate passages through the separator plate, and installing a check valve. This segmentation allows the modification to be performed on existing 46RE/47RE valve bodies without replacing entire components, resolving the contradiction between maintaining simple device complexity and achieving improved line pressure.
Solution Approach 2:
A check valve is introduced as an intermediary component to control fluid flow between the cutback port and the reservoir. This check valve mediates the pressure differential needed to improve line pressure during TCC engagement while maintaining the original valve body structure, thus improving line pressure without significantly increasing device complexity.
2Reliability
If the 48RE transmission valve body is used, then the line pressure increase and TCC engagement performance are improved, but the parts are scarce and expensive
Solution Approach 1:
The invention copies the functional effect of the 48RE valve body by modifying the 46RE/47RE valve body to create the same pressure differential across the TCC piston. By drilling holes and creating passages that replicate the 48RE's fluid communication paths, the modification achieves equivalent TCC engagement reliability using abundant, inexpensive 46RE/47RE parts.
Solution Approach 2:
The modification changes the fluid communication parameters of the valve body by adding holes and passages that alter pressure distribution. Specifically, it creates a direct fluid communication path from the cutback port to the reservoir that was not present in the original 46RE/47RE design, replicating the pressure parameters achieved in the 48RE transmission.
3Speed
If additional fluid communication paths are added to the valve body, then the line pressure response is enhanced, but the manufacturing complexity increases
Solution Approach 1:
The modification uses preliminary action by drilling holes and creating passages in the valve body and separator plate before final assembly. The check valve is pre-installed in the drilled hole, and the separator plate is modified with passages before being installed. This preliminary preparation ensures precise fluid communication paths are established, improving line pressure response speed while maintaining manageable manufacturing precision requirements.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This modification increases line pressure and improves transmission cooling and TCC engagement, enabling the use of abundant 46RE and 47RE valve bodies as replacements for scarce 48RE valve bodies, enhancing performance and reducing TCC wear.
Implementation Method 1
pressurized fluid in the plurality of cutback ports urges the PRV towards a reduced line pressure position
Implementation Method 2
exhausting cutback port 1318 to exhaust 1334 via exhaust passage 1340
Implementation Method 3
boost valve 1306 to open, thereby placing exhaust passage 1340 in fluid communication with exhaust 1334
Implementation Method 4
a spring 1333 that, from the vantage point of FIG. 13, urges the PRV to the left
Implementation Method 5
higher line pressure increases fluid flow through the transmission cooler, thereby increasing heat removal from the transmission
Implementation Method 6
increase the TCC lock-up clutch apply force to help ensure adequate TCC lock-up
Data Source
AI summary
Aspects of the present disclosure include methods of modifying a transmission valve body to increase a line pressure response in certain hydraulic shift control system configurations. In one example, a Daimler Chrysler 46RE or 47RE transmission valve body may be modified to have a higher and more rapid line pressure increase when the transmission is in fourth gear and when the torque converter clutch (TCC) is engaged. Aspects of the present disclosure also include methods of modifying a transmission valve body to allow TCC engagement in any gear. Aspects of the present disclosure also include replacement valve bodies, as well as kits for modifying a 46RE or 47RE valve body to perform like a 48RE valve body.