Front axle disconnect

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caulk04

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Chasing down a variable vibration at highway speeds I have pulled my front drive shaft to test. Upon doing so I found that I cannot turn the pinion of the front axle with the front wheels on the ground. That's not right, right? With the disconnect in the front axle it should allow the pinion to turn and just freewheel internally, correct?

I don't have any errors on the dash and it's in 2wd (BW44-44 case).
 

Wild one

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Chasing down a variable vibration at highway speeds I have pulled my front drive shaft to test. Upon doing so I found that I cannot turn the pinion of the front axle with the front wheels on the ground. That's not right, right? With the disconnect in the front axle it should allow the pinion to turn and just freewheel internally, correct?

I don't have any errors on the dash and it's in 2wd (BW44-44 case).
Nope,driver side axle is still connected to the ring and pinion in the diff.The disconnect only releases the pass side axle.The ring and pinion is always turning if the truck is moving
 
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caulk04

caulk04

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Right, but it's an open diff so shouldn't the driveshaft turn freely? I could've sworn when I dropped the shaft to do my trans bypass that I just turned it to get at the bolts.
 

mtnrider

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Right, but it's an open diff so shouldn't the driveshaft turn freely? I could've sworn when I dropped the shaft to do my trans bypass that I just turned it to get at the bolts.

The ring and pinion does not turn, just the axle shaft. Your driveshaft should turn freely.

.
 
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caulk04

caulk04

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Ok, as I thought. So the collar in there would be stuck? Ugh, something else then since my mystery vibration is still there AND the ujoint of the front shaft doesn't feel right. It's almost as if there's a light detent at center, but no slop. Non serviceable of course.

Here's a video clip of the front shaft, FWIW.
 

Wild one

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I had to go dig out my front diff,and discovered i was wrong,the driveshaft should turn if the axle disconnect is released,so i'd guess your actuator isn't sliding the collar over to disconnect the pass axle.It's been 8 years since my front diff was under the truck,so i'd forgot how it actually worked,lol.
By the looks of your video,that u-joint is getting rough,you might be able to squeeze some grease into it,with a grease needle,but i'd probably replace it,as it's probably ran dry long enough it's due for replacement.
 
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caulk04

caulk04

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Bad part is that u-joint is not serviceable. The joints on the rear shaft are though.
 

Wild one

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Bad part is that u-joint is not serviceable. The joints on the rear shaft are though.
Take it to a driveline shop , they should be able to replace the u-joint,as it looks like heat and a press will push the cups out
 
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caulk04

caulk04

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It's possible, but the factory has the caps peened in. Secondary concern right now anyway, right now I'm wondering about the axle disconnect more. I pulled it off the axle today and mechanically the collar and such is fine, but the actuator may be dead. It pulls power and generates heat at all times and is always extended which is engaged.
 
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caulk04

caulk04

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So can anyone confirm that the front axle actuator should look like this at rest, even when plugged in to the truck with the ignition on? Mine stays in the extended state and pulls power when it's plugged in.

There's also a C147B and C1464 code now that don't clear. Leaning toward replacing the actuator but gathering information.

Couple weeks back we had a real heavy rain I drive in with lots of standing water, during this the check 4wd came on then went away. Later it repeated which led me to check the actuator connection which was very wet inside. I suspect something got cooked in it.

1S12657_4.jpg
 

Wild one

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Do tell then, I didn't see it available/sold anywhere.
Once you remove the old one,you should be able to match it up at your local auto parts store.
FCA will have used a fairly commonly available u-joint,to keep their costs down,so it should be easy to match it up at a parts store.
 
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caulk04

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Got a new front axle actuator today and it seems to be working correctly now.

I knocked the old one apart and it had some corrosion inside which was not surprising since there is no weather sealing other than the plug itself, which clearly allowed water through in my case. It had stuck on, driven the internal mechanism to it's limit and could not return.
 

Wild one

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Got a new front axle actuator today and it seems to be working correctly now.

I knocked the old one apart and it had some corrosion inside which was not surprising since there is no weather sealing other than the plug itself, which clearly allowed water through in my case. It had stuck on, driven the internal mechanism to it's limit and could not return.
Can it be cleaned up and kept as a back-up unit Jesse
 
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