Why do I smell coolant in the cab of my Ford F-250 truck?

[lance]

I have a 2004 F-250 6.0 L Diesel, and I can smell coolant in the cab. I just payed to have the EGR, and EGR cooler replaced, and oil cooler, etc, etc. I don't see any coolant inside the cab from the heater core.

 

[katiesmith]

Shoulda gotten a Chevy

 

[JB]

Sounds like the heater core has a small leak. It may be a very slow leak, but it doesn't take much antifreeze to cause an odor.