Used transmission fluid can be combined with acetone to create a penetrating oil, but success varies based on the type of transmission fluid and its compatibility with acetone. While some users have found it effective for lubrication, particularly in motorcycle chains, others report difficulty in mixing their own formulations. Transmission fluid is noted for its high heat tolerance and cleaning properties, making it a viable option for disassembly tasks. Many users dispose of clean used transmission fluid by mixing it with furnace or diesel fuel, or by recycling it at automotive shops. Overall, while there are alternative uses for transmission fluid, the demand for homemade penetrating oil remains low.