I bought a rebuilt solenoid block for my 2002 300M. Is this easy to replace, or should I take the car to a tranny shop? The tranny shop I called wants $275 to replace it. This includes new filter and fluid. The fluid he uses IS NOT ATF 4, it's synthetic with an additive.
Unless you're really handy and have access to a hoist, i would take it somewhere and have the item installed. It's a messy job, as you have to drop the pan (obviously). You also have to reach up and place the trans in a position that's ahead of "P" (if memory recalls) and that requires releasing the shift cable.
I had my mechanic do mine b/c it's just out of my wheelhouse. As far as the fluid goes, i would just pick up some Mopar ATF+4 from the dealer and have him use that to refill.