205 transfer case guru's needed....

> T-case howl is bad; is it there in BOTH 2wd And 4wd?
> is that the T-case with a chain and center differential?
> are all four tires the same brand, model, size, and inflated to the same pressures?
> are both differentials the same ratios?
I'm no guru anymore, but I have rebuilt hundreds of those, back in the 70s/80s.
Put the Trans in Neutral when it is noisiest; Does the howling stop?
Does the howling change with more/less application of modest power?