1999 whine / howl from drivetrain?

[LukasKO]

Hello,
I need help with diagnosing from where the whine / howl is coming.
I hear this from 0 to 40 km/h, on 1st and 2nd gear, on the other gears I hear it but it is not so loud. It ends about the shift to 3rd gear, it depends on acceleration.
I thought it was transmission, so I decided to rebuild it. I was very surprised when I heard this again... By the way it was a very good decision as planetary was broken - broken I mean damaged - just to say I was lucky...
Here are links with a whine / howl recorded with my old phone.
1st record when the phone was attached to the front of the fuel tank, microphone oriented to the front of the car.
- good tone from 0:20
2nd when phone attached to the frame on the driver side on the line when front wheel ends, microphone oriented to the end of the car.

Now I suppose it is transfer case, but I would like to avoid any unnecessary investments... but when I saw planetary I am afraid this car was not well treated and the same might happen in the transfer case.
I appreciate your help.
PS.
I know, exhaust needs to be repaired too...

 

[XLTrunner]

You sure it's not coming from the rear end? It's pretty common with these vehicles. I can't tell anything from your audios...but, when mine was behaving like you describe here, it turned out the pinion brgs were the culprit. Couldn't believe how it quiet it ran after it was serviced.

 

[LukasKO]

My first record, when I was trying do find out what is going on, I have done on rear end and I found silence

 

[SWIGIN]

If it's a 5.0 it could be the T- case, or with other motors too I guess but the AWD is known for this. Best thing to do if that's it is do a 4406 swap.

 

[LukasKO]

It is 4.0 4WD. I saw 4406 swap tutorial, looks great, but collecting parts can be difficult in my country. For now I prefer to stay with 4405.
Main question - is this t-case?
Is there any option that this sound can become from the engine?