mistereous clunck sound when stay on a hot.....

[balston]

Hy guys i heard a clunck sound comming from somewhere motor or transmision, I live in puerto rico normally the temperatures are 80's to 90's F. it's curious because it happend only when my explorer 2003 stay 8 hours under the sun at working parking. Never happens at the morning or in places where the temperature is ambient. So when is very hot i start the motor then after 2 or 3 minutes i can heard a hard clunck sound comminf from transmision or motor. Any suggestionguys of where to look?

 

[jstorm001]

I get this sound also I have no clue what it is also never effects anything so i never paid no mind to it maybe its the gearbox for 4x4 ? who knows. To me it's like a thud sound when I first heard it I thought an animal was stuck in by the engine.