4LO chirping, diagnose this sound?

[jenos96]

Anyone recognize what this chirping sound might be? Been occurring for
A bit now, no affect on performance far as I can discern

In drive:

In park:

 

[jenos96]

Bump; anyone have thoughts on this?

 

[berry802]

Bump; anyone have thoughts on this?

If its in park and doing this rotational chirping sound I would think it's internal to the transfer case. I don't think anything else would be rotating not including the motor. Does it make this sound only in 4lo?

 

[TakaraLC]

If its in park and doing this rotational chirping sound I would think it's internal to the transfer case. I don't think anything else would be rotating not including the motor. Does it make this sound only in 4lo?

Correct me if I am wrong, but I do not think it can be the transfer case if the it is in park, as no power will be transferred from the transmission to the transfer case.

OP do you get it in reverse and natural as well?

 

[jenos96]

I don’t think I’ve tried R or N unfortunately and don’t know when I’ll next be out.

I do recall reading something about it being possibly caused by ethanol in gasoline… feasible?

 

[TakaraLC]

I don’t think I’ve tried R or N unfortunately and don’t know when I’ll next be out.

I do recall reading something about it being possibly caused by ethanol in gasoline… feasible?

Do you get this in high gear as well? I don’t think an engine related thing would only effect low gear.

 

[jenos96]

Do you get this in high gear as well? I don’t think an engine related thing would only effect low gear.

Yes but less noticeable