Why does my clothes dryer smell like it's burning, even after I cleaned out all the lint?

the lint filter will catch most but not all lint. it's time to take the back off the dryer and vacuum it out. also make sure the exhaust hose is clear as well as the duct from the filter to the exhaust hose. while you're in there check the belt that turns the drum. If you frequently overload, the drum lag during the cycle may burn the belt.