Transfer case clucking

So today I have a new noise,
Whenever I let off the gas or push on gas I'm heading a loud clucking noise,

I put the rear up on the jack and twist the drive shaft and it's coming from tcase or back of the transmission,

Transmission is working perfectly,

It sounds like a bad ujoint but it's not and it's coming from inside tcase or transmission,

What could ot be?

https://youtube.com/shorts/G3YeMbxHB_E?feature=share

 

So couple of things come to mind... First - there is going to be some play and some noise. It's normal. Yours is quite a bit 'louder' than what I have though (just checked). I did completely gut and rebuild my transfer case so all the bearings were replaced but I can't see where that would be it.

I would:

1. Disconnect drive shaft from transfer case, try to reproduce noise grasping the rear companion flange. If not able to reproduce it, then its drive shaft related. I know you said it's coming from the transfer case but it's still something I would rule out. Noises can transmit. Just a thought.

2. Do you have 2-4 selector or is it a j-shift? If it's a 2-4 selector, what happens when you engage it? Does it engage properly and if so, once engaged can you reproduce that same amount of clunk? Shifter is seated and fully engaged?

3. Can you reproduce it with the front drive shaft?

 

It's a j manual shifter, I will see what happens with it in 4x4,
Drive shaft and ujoints are one year old

 

Make sure your transfer case shifter is fully engaged.

The entire rear output shaft is literally connected to the trans. With the exception of that little nub of an input shaft it's all one piece. I just don't see how that would fail.

If it were the chain, well you absolutely would know it. It would make a crap ton of noise slapping about. I wonder if a stretched chain would account for the play and noise you're having (?) @gearcruncher ?

 

Transfer case has 740,000 miles on it

 

Maybe the chain then. If you’ve ruled out the drive shaft and shifter is fully engaged then only thing I can think of is that chain.

 

Assuming it’s the chain slop it’s still probably cheaper getting a used tcase for 400.00 then to have someone replace the chain?

 

Chain is in the ballpark of 300-400 from partsouq. If I can open up the transfer case and gut it, you can easily replace the chain.
A used tcase these days is going to be in or above that range depending on where you source it.

 

Is that side to side slop I am seeing at the output flange? Or is all of the noise generated by a rotational movement? The camera movement makes it difficult to be certain.

 

It’s noise generated by a rotational movement only just like a bad u joint noises but ujoints are good. Letting off acceleration or applying acceleration you hear the noise, if you ease into acceleration you don’t hear it.

 

When in 4x4 there is zero play or movement on both shafts

 

A little better video
https://youtube.com/shorts/SLTamOFL1v0?feature=share

 

Now is that with it in 4WD? That vid seems fine imo. Not sure if I can do it this morning but I'll see if I can get a vid of the same.

 

Update dealership says it's the spider gears from the rear axle sound traveling up to tcase,
Not sure if that means a bad axle or not

 

Zero movement in 4x4

 

They would, wouldn't they $$$ Did you ask them how they diagnosed it?

I don't know. First thing I think of with a clunk on accel or decel is CB and/or drive shaft. I know you mentioned doing it recently but maybe check it again? Looking forward to replies from others to hear other feedback.

Spider gear noise:

https://youtu.be/h452AxoptoA

 

S

Going to go to a diff rebuild shop, spider gears doesn't sound right being the issue,
Maybe transmission

 

On the ground and not driving, mine has a rotational clunk when in 2hi similar to what I'm hearing on that vid. Maybe 10° of rotation. How loud it is depends on how hard I twist the drive shaft. The rotational noise and almost all slop goes away in 4wd.

There will also be some normal spider gear slop but it should very easy to differentiate between the two sources of any type of noise.

 

you need play in the driveline to compensate for heat .
On most vehicles , the play is .8000 of an inch
As the parts inside the transfer case and rear diff warm up . That play will get tighter and tighter .
You got a locker in that rear diff ?
Are you greasing your driveshaft at every oil change ?
In your video , I saw significant play in the splines .
Yoke splines take a special lubricant ...not grease

 

Yes, it's a locker, I took the drive shaft off and it looks like one of the ujionts has a clicking sound, so going to have it rebuilt with sealed Spicer ujoints to see if that's the extra loud noise, drive shaft is not that old but maybe had junkie ujionts