F250 automatic front hubs

I recently purchased a 2005 F250 super duty and the four wheel drive seems to work intermitantly. if i lock the hubs it works, I turned them to automatic and it worked for a while. Now im not too sure how this system works, but I know that that it applies vacum in both steering knuckles when you select 4x4. When I select four wheel drive on the dash within 10-15 seconds my heater goes to defrost and remains there until I put it back into 2wd. Hence a large vacum leak. Do the automatic hubs operate on vacum? or is it something different? if it is what does it actuate?

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Originally Posted by SLAMMDS15

I recently purchased a 2005 F250 super duty and the four wheel drive seems to work intermitantly. if i lock the hubs it works, I turned them to automatic and it worked for a while. Now im not too sure how this system works, but I know that that it applies vacum in both steering knuckles when you select 4x4. When I select four wheel drive on the dash within 10-15 seconds my heater goes to defrost and remains there until I put it back into 2wd. Hence a large vacum leak. Do the automatic hubs operate on vacum? or is it something different? if it is what does it actuate?

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Go to the Ford Truck Enthusiasts forum - they have much to say on the Ford Shift on the Fly front hubs - mostly not too much good, though mine still work just fine on my '06 F350.

http://www.ford-trucks.com/forums/index.php

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Originally Posted by IC2

Go to the Ford Truck Enthusiasts forum - they have much to say on the Ford Shift on the Fly front hubs - mostly not too much good, though mine still work just fine on my '06 F350.

http://www.ford-trucks.com/forums/index.php

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I heard FTE has new management, kinda quit going there a few years ago because Ken tended to ax threads if they made any mention of his banner advertisers competitors. Real paranoid dude, he was.

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Originally Posted by willowbilly3

I heard FTE has new management, kinda quit going there a few years ago because Ken tended to ax threads if they made any mention of his banner advertisers competitors. Real paranoid dude, he was.

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I believe they changed a couple of years ago.

Not my favorite site but have been helpful with problems on my various p/u trucks, including my shift on the fly front end. They have too many 'experts' there that need a life beyond that forum that really have no clue though.

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Originally Posted by IC2

I believe they changed a couple of years ago.

Not my favorite site but have been helpful with problems on my various p/u trucks, including my shift on the fly front end. They have too many 'experts' there that need a life beyond that forum that really have no clue though.

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My brother had bought a new V10 and it was a real pig. I was trying to get some ideas on why but when I mentioned his old 6.0 chevy would out pull the V10 they dogpiled me like you wouldn't believe.

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Originally Posted by willowbilly3

My brother had bought a new V10 and it was a real pig. I was trying to get some ideas on why but when I mentioned his old 6.0 chevy would out pull the V10 they dogpiled me like you wouldn't believe.

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Don't know what year his was but I can assure you that mine isn't - but there were many changes made in late '05 on up (3 valve/cyl) as well as drive by wire and a much better tranny. The earlier V10's needed a good exhaust and a chip to unleash the power. While mine @7400# is not a flash off line, it keeps pulling until it scares the heck out of me. It's possible that he got one of the 3.55 or 3.73 geared versions as well - and they were ..... less then sparkling off line performers :D :D