CharlyE500

Hello guys,
I believe most of CL550 has 4Matic. When you do tranny service, what are the service need to be done for 4Matic ? How much are those service include tranny service ?
Also how hard to change spark plugs and how much should I pay for independent mechanic instead dealer ?

The car has 94K miles and I don't think they were service on tranny and spark plugs.

Thanks