My chevys10 with 97000 miles started overheating last week went all the way up to 240 degreee. I made my way home and after I parked noticed there was something leaking underneath, I believe its antifreeze. Now I can go past 30 miles per hour with out HUGE amounts of white smoke coming out of my exaust also without my temperature going up to 240. And if im just idleing the truck small amounts of white smoke still come out with a good amount of water dripping off my exaust, I had a problem with my truck overheating before and changed my thermometers, now what is the problem? Blown head gasket? Oil problem which I doubt because I changed it ever 3000 miles on the dot. Cracked radiator?
Continuous white smoke after the engine has warmed up is a sign of coolant entering into the combustion chamber. Where it is leaking from is what needs to be determined. The engine is overheating because it is low on coolant due to this leaking.
Possible causes of the leak are: intake gasket, head gasket, warped or cracked head, and cracked block.
If you tell us what engine size you have, one of us may be able to tell you what is common with this engine to cause white smoke.