I own a 95 F-150 XLT with 4.9L I-6. I have blown 2 radiators in the last 2 years and I don't know why. The blow outs are in the same place, the main hose on the upper driver side of the radiator. When I changed out the first one, I also changed the thermostat. The second radiator I put in came out of a 95 F-250 and was a double core heavy duty. Both times the radiators have blown while climbing up mountains, but were not loaded down to much. The first time I was heading camping with my family without towing a trailer, and the second time I was getting rid of old shrubs that we pulled out. Any ideas of what to check will help. I am deployed to Afghanistan and have not had a chance to look at the results of the second blow out or know what the truck was doing before it went. But the first time it happened the temp gauge went from normal to hot in a matter of seconds then the radiator blew. Thank you for any help that is given.

 

You're more likely to get help if you fully describe your truck/mods, engine, and offer some detail as to how and when the problem was found and what you have tried and ruled out. Just a suggestion.

 

He is in the six cylinder section.

I blew out my radiator when I continued to drive the truck with a cracked head. Blew out in the same spot.

 

Sounds like the second one was used and depending on the part of the country you live in, plastic gets brittle and cracks with age. My 93 F150 had a slow leak in the same spot. I replaced it with a brand new one and haven't had any problems since.