Interesting Facts from the ETE REMAN blog...
(Explains the reason why I've always emphasized that everyone should cap their Trans dipstick tube!)

The W5A580 is extremely sensitive to the quality of the transmissions fluid. Even with the slightest hint of water in the fluid (as low as 0.05%) the transmission can start shuddering. If you experience shuddering with your transmission, try changing out the fluid with new fluid and be sure to replace the internal filter, too. In my opinion this transmission is the perfect candidate for an aftermarket external transmission filter. The aftermarket filters are designed to work with the factory internal filter still in place. The aftermarket filter is usually placed in one of the transmission cooler lines and uses a filter element similar to ones used for cleaning engine oil. They are specifically designed to trap fine debris and water.
Water getting in around the dipstick tube is another problem and is directly related to the problem above. The problem is usually caused by a defective O-ring. The O-ring can also be the cause of fluid leaking from the transmission, too. The cure is simple. Replace the O-ring with a new, upgraded O-ring. It will take you longer to get the car up in the air to work on it then it will take you to replace the actual O-ring.
Source: custom magnums.com

There have been a few complaints about the torque converter clutch not holding correctly. The problem could be caused by a defect clutch inside the torque converter, transmission fluid contamination or a faulty solenoid. The problem is not wide spread but you should be aware of the potential for it to arise.
Overheating from excessive abuse is another thing to watch out with these transmissions. The cars that this transmission is usually placed in are all high performance models. The owners think they can abuse the transmission with no side effect. They are wrong. Transmission abuse will lead to excessive heat buildup and if not kept in check, will quickly destroy the transmission.
Source: benzworld.com

Here are a couple cool facts about the W5A580:
- It uses a torque management system that is designed to make the transmission shift smoother.
- The ECM is programmed with drive recognition software that helps customize the shift points based on how you use the cars braking system and how you interact with the gas pedal.
The W5A580 is designed to last for a long time with proper care. If for some reason your W5A580 transmission fails, seriously consider replacing it with a re-manufactured transmission over one that was simply rebuilt. A re-manufactured transmission will include upgrades and modifications designed to make them last long and will usually come with an extend warranty, neither of which you will find in a rebuilt transmission.

More info:
Mercedes NAG1 / WA580 automatic transmission for Dodge, Jeep, and Chrysler

From the Lubricants Database:
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