I'm a first timer here to the Ranger forum. I own a 1994 XLT Ranger 4x4 4.0 with approximately 112k miles.
This past week I let my daughter drive the truck for a road trip. The trip is about 200 miles nearly all of it interstate. The start of the trip is at or near sea level. The end of the trip is about 3300 ft above sea level. So, you can see that near the end of her trip she was pulling up some steep hills. Anyhow, she ran into a problem with the truck overheating. I had her check the fluid, which was low, so she replaced it. The problem was solved for a short period of time. However, the overheating soon came back, again from the lack of coolant. I had her look the truck over to tell me where the leak was coming from. She wasn't sure
So, I told her to keep and eye on the temperature and replace the coolant as needed until she got home.
After my daughter made it home safely, we started talking about the problem. She told me the truck was no longer overheating and no longer losing coolant. This got me to thinking, "How would the change in altitude cause the coolant to leak out?" We've been driving the truck for several days now, and the truck runs fine and the temperature stays normal.
I know altitude affects boiling points and pressure, but do you think this is the cause of the problem? Any thoughts are appreciated. BTW, I plan on checking/replacing the thermostat, radiator cap, the fan clutch, overflow tank, and hoses. Any other things that I should look for in this situation?