Driving down the highway, Or just plain driving on back roads, and especially during hard throttle my truck makes a ticking sounds almost sounds as if its the thermostat chattering. but i have no idea what it could be?It wont do it in neutral so im almost thinking it could be in the tranny? it doesnt sound like a lifter taping but it is really bothering me i still have a 3 years worth of warranty left or 45000 miles. im thinking i may take it in and have it looked at but does any one have any opinion on what it might be?