Dust coming in the vents

[EArmsF350]

In the last couple of weeks I have been dusted out of my cab with dust from the rock roads. I travel 100's of miles a week on them because I am a farmer. I cannot figure out why this dust all of a sudden starting coming in through the vents. It will stay out of the cab if I keep it on Max AC and the fan on high. Comments, Answers?,,,,,

[JSchuricht]

Max AC recirculates the air. Everything else sucks it in from the outside. I would look into making some sort of filter to trap the dust.

[Maverick1701]

Originally Posted by JSchuricht

Max AC recirculates the air. Everything else sucks it in from the outside. I would look into making some sort of filter to trap the dust.

^ this

as long as its on max you are good to go

[jacobm24]

I have mud-dobber nests inside my ac vents so I get dust coming out quite often... long story

[EArmsF350]

I've never had this dust issue before. The truck has 235,000 miles on it. All of a sudden Im dusted out. Usually never run the AC or the vent. Defrost on frosty mornings and of course the floor heat all winter. I will get dust with everything but Max AC. I still dont understand. Just started a couple of weeks ago....

[forddieseldoctor]

Pull your blower motor out and see what's in there for dirt. Also pull off your wiper cowl. The air inlet is below that.

We get concrete company trucks in for service and after the first couple of times you learn real quick not to turn the vents on high unless you want a dust shower. I also learned the hard way no air tools in the cab.

[jesilvas]

Same. Max AC pulls air from the passenger floor board, all others is in from the cowl between windshield and hood.

I think there is an option from Ford to add a cabin air filter.

[EArmsF350]

But why would I all of a sudden get all of this dust? It's like something broke. I'll have to talk to a service rep and see if they would know.

[jesilvas]

They'll probably say the same thing.
Is the blower motor sounding different, blowing differently, or has anything changed at all? Other than the dust?

[EArmsF350]

Nope, everything is the same. The only place the outside air comes into the cab is by the wipers? I dont get dust up there so I cant imagine that would be the problem. I am totally stumped.