I would think so, I cant imagine the plugs or anthing else is different. I may just try to find a wrecked GS and see if I can get my hands on this. Having had the 5th gen in the IS its a nicer system hands down but I can live with what I have now. Not sure it would be worth putting a lot of time and $$ into??

 

where can you find a wrecked GS?

i called a local lexus dealership today and they said they need the vin number of the car and blah blah blah. he also said that it's not possible to install a gen5 nav on an 06' with gen4 nav.