 I have already taken my '08 Toy. 4Runner 5 times to 3 different Toyota dealerships for service... they've changed my catalytic converter and I still have a problem with my exhaust and emission system of this car.  When I drive it in the highway in the speeds of 60 MPH and faster I get a real STRONG and HEAVY sulfuric and ammonia scent entering inside of the vehicle which gives me a headache and bothers my newborn baby.  I basically cannot drive this automobile with my windows down!!!  Toyota service is the worst that I've ever seen!!!