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vacume leak ?

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Old Jul 14, 2009 | 07:51 PM
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vacume leak ?

well i was out at my deer lease this weekend and used my 4x4 and the a/c went to the defrost. and from what i have read today i have a vacume leak.
i have nottaced for a few weeks when i switch the a/c on it takes a long time for the door in the vent to switch to over and when it does it thuds like it is building vacume this slams.
also i could not turn the shaft going into the hub. weather it is in 4x4 or not. does this mean my 4x4 is locked in. i checked the hubs and they or in auto.
and also there is like a plastic ring that is loose and will spin around, down by the nuckle going into the axle tube.
would it be a pain to just plug the lines at the siloniod and just go with manual locking hubs like warn.
thanks.
Don Smith
 
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Old Jul 14, 2009 | 09:00 PM
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You can plug the lines and go manual hubs, but you've got bigger issues than that. Sounds like the big seal in the knuckle failed (plastic ring spinning around). If you want to keep water out of the expensive unit bearings, you'll need to tear it down.
 
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Old Jul 14, 2009 | 09:15 PM
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sounds like iv got something to work on.
i need to make sure its the hubs with the vacume leak.
ill have to do some more searching to find how to narrow it down.
but ill have to fix the seal.
 
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Old Jul 14, 2009 | 09:21 PM
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Originally Posted by tigwelder
sounds like iv got something to work on.
i need to make sure its the hubs with the vacume leak.
ill have to do some more searching to find how to narrow it down.
but ill have to fix the seal.
Here is a thread to help you narrow down where the leak may be. LINK
 
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Old Jul 15, 2009 | 04:56 AM
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thanks that will help alot.
any ideas why my axle shafts wont free turn WHEN 4X4 IS NOT ON. i could not turn the u joint parts inside the nuckle.
 
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Old Jul 15, 2009 | 08:53 AM
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Are your hubs in "auto" or "lock"? If the writing is worn off, counter-clockwise is "auto" and clockwise is "lock". If you are in auto and the shafts won't spin, my guess is you have one of your auto-locking hubs is frozen.

This problem seems to be cropping up a lot lately (gotta love the ESOF!). Here's some recent links that might help:

https://www.ford-trucks.com/forums/6...rt-number.html

https://www.ford-trucks.com/forums/8...o-i-start.html

https://www.ford-trucks.com/forums/8...king-hubs.html

https://www.ford-trucks.com/forums/8...-solenoid.html

That should be enough to chew on to get you started...

Best of luck!
 
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Old Jul 15, 2009 | 11:49 AM
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i looked last night and my hubs are in auto.
how bad is it for my front and to be turning all the time, like at highway speeds.
and, both sides wont turn.
thanks
 
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Old Jul 15, 2009 | 11:51 AM
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If the hubs are in auto the front end shouldn't be turning. Won't hurt much except for your MPG's.
 
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Old Jul 15, 2009 | 12:47 PM
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i thought you werent supposed to drive over like 50 in 4H? i just recently replaced my wheel bearings and 1 4wd hub and breaking down the hub is easy anyway, just pop the snap ring off and pry the inner ring out and everything should just pop out but just pop the hub out and try to turn the inside shaft input before you do all that and if it doesnt turn then its locked up and you can get an easy rebuild kit for it or buy a new one... if the hub is the problem then thats a quick 5 minute test at least.
 
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Old Jul 15, 2009 | 01:14 PM
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Originally Posted by mudbug04
i thought you werent supposed to drive over like 50 in 4H? i just recently replaced my wheel bearings and 1 4wd hub and breaking down the hub is easy anyway, just pop the snap ring off and pry the inner ring out and everything should just pop out but just pop the hub out and try to turn the inside shaft input before you do all that and if it doesnt turn then its locked up and you can get an easy rebuild kit for it or buy a new one... if the hub is the problem then thats a quick 5 minute test at least.
Having the T-case in 4x4 and having the front hubs locked are 2 totally different animals.
 
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Old Jul 15, 2009 | 01:24 PM
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my bad i thought he was worried about his hubs being possibly stuck too, i dont know anything about the transfer case i have never had to go into that yet (knock on wood).
 
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Old Jul 15, 2009 | 01:26 PM
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Originally Posted by mudbug04
my bad i thought he was worried about his hubs being possibly stuck too, i dont know anything about the transfer case i have never had to go into that yet (knock on wood).
No worries, asking questions is how you learn.
 
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Old Jul 15, 2009 | 01:36 PM
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so if the tcase is messed or if i was just driving in 4wd is it actually safe to drive at higher speeds 50+ constant? sorry about gettin off his subject about how to solve his problem, but now im curious...
 
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Old Jul 15, 2009 | 01:53 PM
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Driving on a hard road in 4x4 at high speeds is gonna tear stuff up... especially if you are turning. If its just that your front hubs are sticking and the axle shafts are turning don't sweat it, you won't hurt anything until you can figure out why the hubs are sticking and fix it.
 
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Old Jul 15, 2009 | 02:10 PM
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Lot's of guys up North lock the hubs for the winter so they can engage whenever they need it. No problems that I know of except lower MPGs...
 
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