Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges

No.19 excessive shift shock on torque converter clutch (tcc)

No.21 noise occurs at idle when vehicle is stopped in d, s, l ranges, or in r position

Other materials:

Mazda 6 Service Manual: Recommended Oil
U.S.A. and CANADA Use SAE 0W-20 engine oil. Mazda Genuine Oil is used in your Mazda vehicle. Mazda Genuine 0W-20 Oil is required to achieve optimum fuel economy. For maintenance service, Mazda recommends Mazda Genuine Parts and Castrol® (U.S.A. only). Only use SAE 0W-20 oil “Certified F ...

Mazda 6 Service Manual: Front seat disassembly/assembly
Warning Handling the front seat (side air bag) improperly can accidentally deploy the side air bag, which may seriously injure you. Read AIR BAG SYSTEM SERVICE WARNINGS before handling the front seat. (See SERVICE WARNINGS.) 1. Disconnect the negative battery cable and wait for more tha ...