Just some things you should check:

Expansion cap.
Thermostat (for the M104 is rated at 87C)
Aux fans (high speed), starting at about 105C
Fan Clutch (you can test it, do a search on that).
Cooland leeks (do you have to add coolant frequently?)
Water pump.
Last thing is a cloged radiator.

System flush is recomended every 3 years.

Regards,

Juan

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter