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Discussion Starter #1
I have 2005 4.8 with what I believe is a transfer case issue. Can some who has had the case apart tell me what part failure would allow the front and rear wheels to be come disconnected from the transmission. The failure happen at stop light (no go D or R) with no previous transmissions issues and the odd problem the car will roll freely in park.
I understand how broken chain or stripped front splin allow front wheels to be free. How is rear
Free. I saw a few post with transfer case issues that left car immobile and rolling in park.
 

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Discussion Starter #2
Found it

Transfer case is using a planerary gear set that will allow rotation of the rear drive shaft when the front is free(broken chain or splines)and transmission is locked. I was thinking of the viscous coupler transfer case that will hold rear shaft if the front is free. I need a transfer case!
 

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Discussion Starter #3
No do not have answer

Well I now have read tech documents that say the 2005 uses clutch packs not plenitray gear set. Documents say packs when fully engaged send power 50/50 front/back. As pressure is reduced on clutch by actuator it can go to 0/100 front/back. Based on input and conditions can be anywhere in between. Point is rear is always engaged so how can car role free in park and have no go in D or R. No previous transmission issues at all just dead at traffic light one morning. If I put car in R and go to P it grinds unless you wait a few minutes. I believe that is telling me transmission shaft is spinning with no load and I must wait for it to stop. Am I dealing with transmission or transfer case issue and how do I pin it down? Any insight would be great
 

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Discussion Starter #4
Rear differential

Problem is a rear diff failure. Drive shaft is rotating and the wheels do not turn. Very odd failure and the diff makes no noise. You can see in the attached photo the axle shafts have pulled out of the diff and disconected. Very very odd failure. Can not understand what failed that would let the axles pulll out of the differential carrier
 

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