Is this Normal?

[94Fexplorerxlt]

When I'm out driving in the country when I go up steep hills and mountains I notice my temp gauge goes up to about "A" on the Normal gauge. On basic roads I'm riding on the "O" of normal. I never really paid much attention to the gauges growing up so Im not sure if its always done this. I just replaced my radiator last week too.

 

[natenkiki2004]

Temp will definitely go up under higher loads and slower speeds. I don't know if mine swings that much but it moves a noticeable amount transitioning from hilly gravel roads to flat pavement. I'd be concerned if it stuck on or went past L.

 

[4x4junkie]

Mine does that (starts going to the "A" or above under load) when the coolant starts getting too old. A complete system flush with Prestone Super Flush and then new coolant has always fixed the issue (the gauge pretty much stays right about between the "R" and "M" of "NORMAL").
You did say you just replaced the radiator, so I would assume that includes new coolant also... Maybe there's still some gunk elsewhere in the system that's restricting the flow of coolant?

 

[Anime]

Did you change the thermostat when you put in the new radiator?

The thermostat may be on it's way out, and might just be stuck in one position, so it's open enough or a little too much for regular driving, and not enough when going up steep hiils.

Some cheaper thermostats can also let the temp gauge needle swing like that because they have a weak spring and don't really maintain a constant temperature like higher quality 'stats.

If you didn't replace the thermostat, now would be a good time. If you replaced it with something cheap, you might consider something better. The 195 degree Stant Superstat is a good choice.

You can also get temperature swings if the coolant/water mix isn't what it should be. 50/50 coolant/water is ideal. One gallon of coolant is all you need in the system, with the rest water, since the system holds just over 2 gallons. Too much coolant can actually reduce the heat transfer when the engine gets hot.

 

[Wolfie_85]

Don't freak out too much, unless it doesn't go back down after a while of easy driving on a level road.

 

[larrydd999]

I agree with all of the above, having seen the problem. One other consideration is whether the fan clutch is working properly.