Radiator blower fan always comes on the first time I pull onto the highway

[-cycosis-]

I dunno if this is normal? I have a 5.9L cummins turbo diesel with an allison at545 transmission.

Regardless of it being hot or cold, every time I first go on the highway, the engine will heat up to over 220 and then the cooling fan will turn on for about 2-3 minutes, bring it back down to 210 and then it will shut off.

Every time.

Is this normal?

[o1marc]

Does it maintain temp after the initial heat up period? if so, sounds like a bad thermostat. 220 is hotter than I like to see during normal use.