Manual transmission and dry clutch transmission (dDCT) fluid testing is used to test and evaluate manual transmission fluids. There are two types of transmission fluids: automatic transmission fluids (ATF) and manual transmission fluids (MTF). Transmission oil is critical to keep gears lubricated. At SwRI, we conduct a number of transmission fluids testing for both ATFs and MTFs.
Manual Transmission and Rear Axle Gear Lubricant Performance Testing
Required bench and performance tests are conducted to qualify automotive gear lubricants under various specifications. Numerous other test procedures for the lubricant and additive industries may be conducted, as well as custom programs tailored to clients’ individual needs.
L-33-1 Moisture Corrosion Test (ASTM D7038)
To determine the corrosion prevention properties of gear lubricants, an axle is filled with test lubricant and distilled water and operated for four hours at 2,500 rpm and 180°F, then soaked for 162 hours at 51°C (125°F). The axle is then disassembled and rated for rust. This test is referred to in FTMS No. 791, MIL-PRF-2105E, SAE J2360, API GL-5 and Federal Test Method 5326.1.
L-37 High-Torque Test (ASTM D6121)
To determine the load-carrying, wear, and extreme pressure characteristics of gear lubricants, a test axle is operated under low-speed, high-torque conditions. A test axle is operated for 24 hours at 80 axle rpm, 135°C (275°F) lubricant temperature and a high ring gear torque. This method is referred to in FTMS No. 791, MIL-PRF-2105E, SAE J2360, API GL-5 and Federal Test Method 6507.1.
L-42 High-Speed Shock Axle Test (ASTM D7452)
This high-speed shock test determines a lubricant’s ability to prevent coast-side pinion and ring gear scoring. The axle torque and coast down rates are measured and recorded. This method is referred to in FTMS No. 791, MIL-PRF-2105E, SAE J2360, API GL-5 and Federal Test Method 6507.1.
L-60-1 Thermal and Oxidative Stability Test (ASTM D5704)
This method determines lubricant deterioration under severe thermal and oxidative conditions. A set of spur gears is rotated at 1,750 rpm for 50 hours. The lubricant is maintained at 163°C (325°F) with controlled airflow in the presence of a copper catalyst. The physical and chemical properties of the lubricant and deposits on the test gears are evaluated at the end of the test. This method is referred to in FTMS No. 791, MIL-PRF-2105E, SAE J2360, API GL-5, Federal Test Method 2504 and API MT-1 (ASTM D 5760).
FZG Gear Wear Test (ASTM D4998)
To evaluate the anti-wear properties of lubricants, particularly hydraulic fluids for tractors, test gears on the FZG rig are operated at 100 rpm for 20 hours at 121°C (250°F) and load stage 10. The gears are weighed before and after the test and the weight loss associated with wear indicates lubricant anti-wear performance.
FZG Load Stage Test (ASTM D5182)
Various speeds and temperatures are available to evaluate the load-carrying capacity of lubricants. The variable speed FZG test rig runs through twelve 15-minute stages with incremental increases in load until failure or until the test sequence is complete. Twenty millimeters of tooth scuffing indicates test failure. This test method is referenced in API MT-1 (ASTM D5760) and other OEM specifications. The CEC L-07-95 load stage procedure can also be run. (DIN ISO 14635-1)
FZG Pitting Test with Type C Gear
This test procedure is used to discriminate different lubricants based upon their ability to prevent pitting, a fatigue failure due to rolling contact. The test consists of a break-in phase and a durability phase. The test normally runs 300 hours and is usually carried out in triplicate to cover outliers.
FZG Step Load (A10/16.6R/90:120)
This test procedure (CEC L-84-02) is for industrial or automotive gear lubricants that exceed the load-carrying capacity of the standard FZG load stage test (A20/8.3/90) (CEC-L-07-95). The smaller 10 mm wide gears are run in the reverse direction at 2910 rpm through twelve 7.5-minute stages with incremental increases in load until failure or until the test sequence is complete. The test can run at either 90°C or 120°C (194°F or 248°F). Ten millimeters of tooth scuffing indicates test failure. A pass in load stage nine at 90°C (194°F) indicates GL-5 or better performance. The FZG shock test procedure (S-A10/16.6R/90) can also be run.
FZG Micro-pitting Tests
Various test procedures are available to determine the influence of lubricants on the micro-pitting load carrying capacity of gears. Test procedures include FVA 54 and Eaton Engineering Procedure TEP-272.
FZG Verschleiss Test
This test procedure is used to determine the wear protection characteristics of fluids for gears run at low speeds.
Manual Transmission High-Temperature Cyclic Durability Test (ASTM D5579)
The high-low range synchronizer of a Mack T2180 transmission is cycled with lubricant temperatures at 121°C (250°F). The shift time is monitored continuously during the test. As the lubricant degrades, the shift time increases. The test continues until two “missed shifts” are reached or until the test sequence is complete. This test is part of Mack Trucks, Inc., Gear Oil Specifications GO-H and GO-H/S as well as API MT-1 (ASTM D5760).
SSP 180 Synchronizer
The purpose of this test is to evaluate the frictional performance of a lubricant in a synchronizer assembly. The test is conducted in an SSP-180 test machine. The synchronizer is loaded by a flywheel that is accelerated and decelerated between rest and top speed. Test conditions are dependent upon the type of synchronizer tested.
Axle Efficiency Test
SwRI has stands designed and constructed to accept various types of rear-wheel and front-wheel drive axle assemblies. These stands have the capability of programming test procedures/profiles specifically designed by clients.
OEM Test Procedures
Many OEMs call for modified versions of some of the axle tests listed above. SwRI can perform the modified tests for these procedures and act as an intermediary for OEM contact when requested.
Mack GO-J/J+ and Eaton Test Procedures
Mack, Dana, and Eaton call for modified versions of some of the axle tests listed above. SwRI can perform the modified tests for these procedures and act as an intermediary for OEM contact when requested.
Manual Transmission and Dry Dual Clutch Transmission (dDCT) Fluid Testing
General Motors Dry Dual Clutch Transmissions Fluids Testing
SwRI conducts the following procedures associated with the General Motors DEXRON®- Dry Dual Clutch Transmission (dDCT) Gear Box and Manual Transmission Fluid Specification.
DEXRON®-dDCT Chemical and Bench Tests
These procedures include tests to evaluate dry dual clutch and manual transmission fluids for appearance, elemental content, water content, fluid profile, miscibility, density, storage and compatibility characteristics, high- and low-temperature viscosity, pour point, flash point, total acid and base number, copper corrosion, oxidation stability, shear stability, volatility, anti-foaming properties, film thickness, and effects on seals.
DEXRON®-dDCT Wear Test
Anti-wear characteristics of dry dual clutch and manual transmission fluids are determined by running an Eaton 35VQ25A vane pump test. Performance is measured by measuring weight loss of the pump’s vanes and cam ring.
DEXRON®-dDCT Scuffing Protection Test
The FZG Step Load (A10/16.6R/90) test procedure is used for fluids that exceed the extreme pressure characteristics of the standard FZG load stage test. The smaller 10 mm wide gears are run in the reverse direction through 12 7.5 minute stages with incremental increases in load until failure or until the test sequence is complete. The test is run at 90°C.
DEXRON®-dDCT Synchronizer Function Test
The purpose of this test is to evaluate the frictional performance of a dry dual clutch or manual transmission fluid in a synchronizer assembly. The test is conducted in the SSP-180 test machine. The test lubricant temperature is controlled while the synchronizer is shifted. The synchronizer is loaded by a flywheel that is accelerated and decelerated between rest and top speed. The test conditions are dependent upon the type of synchronizer tested.
For questions about this testing, please contact Rebecca Warden at +1 210 522 6266.