I live in the desert and my 98 Dakota 4 cy 2.5 can not handle the summer temps...120 today. Does anyone know what is the largest size radiator that can fit without doing alot of modifications. It only overheats when the temp is over 100-105 degrees. Everything is new as far as the entire cooling system. I have changed everything, the only thing left to try is a larger radiator...I think. Any suggestions or recommendations would be greatly appreicated. Melting with my Dakota.

 

I can't answer your question definitly, but can can provide some suggestions.
Perhaps you can see if a raditator from a Dakota V6 or V8 will fit.

Before you delve into a new raditor, do this:
"Everything is new as far as the entire cooling system. I have changed everything" What temperature thermostat did you use? Try a 180degree or 160degree.
Wire the fan so that it comes on when you start the truck (instead of at a certain temperature, like it is stock).

Post back with results or for more information.

 

I agree with the 180 degree t-stat suggestion. Also, did you have the coolant system flushed completely? The engine block can build up with a LOT of debris and sediment over the years, and it's good to get all that cleaned out of there.

I also agree that wiring your fan up to a switch would be a good idea.

 

Using a cooler t-stat only delays the inevitable by a few minutes; it doesn't really fix overheating. For now, try a different mix; Flathead Ford V8 (engines notorious for overheating) fans like to use 3 parts water to 1 part antifreeze; the water deals with the heat better, but this still leaves enough coolant in the system to prevent corrosion or freezing on cold desert nights.

Check out this site http://www.carnut.com/tech/tech.html and go to the bottom for some interesting cooling tips. Hope this helps.