My temp light comes on after riding for 20 minutes. I changed the oil, the radiator if full. I have 98 454 4x4.

 

Is your thermostat opening up and letting water cir. though the engine check the rad. out for water movement . 2 nd check out the temp light switch it is a little brass single wire switch

 

You need to find out if the engine is actually getting hot. Does it smell hotter than normal? Does the engine seem to be radiating more heat? I have an infarred temp sensor that I check temps with. Last time I had a temp light on the engine temp was only 197 degrees. The temp sensor was bad. Even a short can turn on your light so first find out if it is really hot.

 

smell hotter? put ur face on the header, if it burns, its hot. [img]i/expressions/face-icon-small-tongue.gif[/img]

 

I like that! LMAO But you better be careful, some dumba$$ will do it.