Ok. Lexus, Caddilac , Benz etc. Will they need deadning since they already deadned, exept for the trunk.
And Rudy is right about butyl vs crap. My Car has OEM patches of butyl in the trunk and under pass seat. Its 10 years old and it looks like it was installed today. Its soft and stretches like warm chewing gum.
Modern luxury cars will need much less sound deadening than others. They are already very good a blocking sound from the outside, so you generally don't even have to think about that. What you need to remember is that they are deadened for optimal results with the factory sound system. If you change that - adding Power and drivers in other locations than stock, you will probably want to reinforce those areas.
Tearing a high end Car apart is a great way to learn about sound deadening.
if you want you can add it i guess it wouldnt hurt, but i learned my lesson with lexus cuz they messed me over on my IS F, i had two 12's and the door sensor for the keyless entry fried and they said it was the audio fault and charged me 2500 to fix it, which isnt true. but they like to blaim on crap you do to your car so they can make some money off of you. with the factory deadening it bairly had any raddles, just tighten up the trunk locking thing.
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