Curious if anyone has had a similar problem, bought this vehicle a couple weeks ago and has a lifter tick as to what the old owner was a rod knock. yay me lol, engine has a lot of oil sludge build up, going to flush the engine real good and see if maybe its stuck. If not then going to replace the tappets and timing chain. Im mechanically inclined so ill be doing the work. Haven't really heard of the 3.5s having major engine issues.