Has anyone added a seat subwoofer, and how is the effect?

The maintenance manual for the Arrizo 5 suggests adding 4.7L of engine oil, but most services on the market typically charge based on 4L. Has anyone tried only adding 4L?

Guys, can the rear seats be replaced with aviation seats? Has anyone done this modification?

Dear car enthusiasts, has anyone added a catalytic converter cleaner to the fuel tank of a 2011 manual Touran? After I added this kind of cleaner, it started emitting white smoke and the check engine light came on. Has anyone experienced this situation?

Has anyone replaced the door seals? How's the effect? The wind noise is getting louder.

Hey folks, has anyone added a Zengcheng battery pack?

Has anyone added a seat subwoofer, and how is the effect?

Is there anyone who has added rear air vents for a small car? It's really hot in the back seat.

Has anyone ever modified their ACC after getting their car? I want to ask how effective it is.

Has anyone added through-type taillights to the 2023 Villa model?

I've got a 2014 Peugeot 3008 1.6T that's been burning oil. I've added three liters of oil in the past 5000 kilometers. I'm thinking about replacing the valve seals. Does anyone know if this works? Has anyone else done this, and how effective was it?