I've been doing some research on the site, and have seen a few posts that reference sludge buildup. I know that the 2.7L motors from Chrysler had a huge problem with sludge buildup, but I did not think the same applied to the 3.5L motors.

Does anyone know if the 3.5L motors have an issue with sludge?

 

Not that I've heard of. I have an '05 that I bought 2 years ago and I drive it quite frequently and I've yet to notice such problems. Keep in mind, people who take care of their cars won't have such problems. For example, my father in-law owns a Kia Sedona and he doesn't maintain the car. When I last checked is oil, the dipstick was full of sludge. So like I said, if you check your oil on a regular basis, you won't run into or your engine won't be a "sludge" engine