The V6 has the Mercedes W5A580, which has no dipstick, just a plastic cap on the tube for the dipstick.
The Mercedes W5A580 does have a special tool that is a dipstick, to check fluid level. The trans is very sensative to fluid level, more so than other trans, so they make it a Dealer/Shop service item only and do NOT include a dipstick.
You can find the dipstick tool on e-bay and other places, it is a tool, NOT designed to stay in the trans like other dipsticks. You pull the cap and put it down the tube and a good portion still sticks out after it bottoms out. So no, after you get the special tool, you can't leave it in the trans like its a regular dipstick.
The procedure for checking the trans fluid level is to use the dealer starscan tool, or another enhanced scan tool that can access the electronics of the trans and read the trans temp from the sensor. Then look up the proper fluid level vs temperature from a table in the FSM, you can find them on the internet as well, and measure that level with the special tool. (See why they made it a dealer/shop only service item.)
If you don't have an enhanced scan tool that can read transmission sensors, you may be able to still use the special tool dipstick, using an accurate temp measure tool against the trans fluid pan.
2006 Steel Blue 5.7L HEMI Limited 4x4 Build Date: June 9, 2006 Hour 14
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