Drive shaft slipping and clanking

vgrn

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Any idea what transfer case this is? Every time I put the vehicle in reverse the rear drive shaft clanks/slips. Also everyone I’m driving and give it some gas it also clanks/slips. Some one test is knowledgeable with square bodies said that it’s probably the transfer case. Any ideas?
 

Vbb199

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Looks like a np203, but im not a t case expert
 

Octane

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It looks like to me a Np203 chain driven fulltime unit.Chains can wear out and cause clunking and chain noise.Mine never has tho.As far as slipping,I dont know unless its actually jumping its chain gears.I would think if it got that bad it would fail completely very soon.
 

Turbo4whl

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Yes, Vince is correct, 203 transfer case. The common failure is a stretched chain, then it jumps over the drive cogs and slips. If the rear U-joins are tight then you hear the noise amplified by the rear drive shaft.

The chain drives the front drive shaft, but it is located at the back of the transfer case. Has the system been modified to part time? Unlocking front hubs?
 

75gmck25

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Are you sure it’s the rear driveshaft?
With an NP203 the front driveshaft has a CV joint (double u-joint) on one end and a regular u-joint on the other end to handle the driveshaft angles as the suspension moves. If they dry out you get quite a bit of noise out of them.
 

Octane

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The front shaft cardon joints can go dry,there is a fitting for grease on them.(Two u joints with a shaft betwixt them).When they wear out they get noisy.
 

el chevy

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Mine does the same thing put in reverse clank loud that’s the only gear it does it with it’s a 2wheel drive though hope you find solution so I can get mine fixed thank you
 

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