Slight Drivetrain Whine, Is This Normal?

Starting about a month ago I noticed a slight whirring/whine sound coming from the final drive portion of the drivetrain. Its "noticeable" and may be normal, I'm just not sure. Its a fairly faint sound, almost like the meshing of the gear teeth. Its odd that the first 65,000 miles of the car's life the sound was not there. I say the "final drive" because the tone of the noise varies directly with road speed, not the engine speed. If I shift gears from 5th to 4th, the tone is the same, although its quality is slightly different. I do think it is coming from the transaxle.

Its most noticeable when in 4th or 5th gear with a very slight loading of the engine. Push the accelerator slightly more, the sounds fades out, or let off the accelerator (engine over-run), the sound fades out too.

If abnormal wear is causing the sound, there are only two causes related to me I can think of:

1. I coast in neutral alot. Up to lights when I need to only slow gradually, coming up to turns and turn and put it in gear again, etc. I wonder if this in some way could damage the transaxle by preventing proper lubrication (slinging the oil inside) of the geartrain.

2. At 50,000 miles I changed the gear oil (with the same G052 gear oil) and only put 1.5 liters back in (that is all it would hold when I leveled the car, but I forgot to run the car in gear for a few minutes and recheck the level, per Bentley) and I wonder if the transaxle is a cup or two too low, but I reason even if slightly low, this should not cause damage.

Any thoughts? Anyone elese have this slight drone from their transaxle that I hear? Its almost a normal sound, but I've only noticed it recently.

Thanks.

--Nate

Bump.

Anyone?

I think I read a TSB somewhere about a change in VW gear oil because of noisy transaxles.

I plan to recheck the oil level in about a month, just before I remove the transaxle to install a G60/VR-6 clutch (the stock one is slipping at 70,000 miles because of the RC 1).

--Nate

I have the exact same whine. It only happens in 4th and 5th. Mine started whining at around 68k. I now have 84k and the whine hasnt changed, although it is still there. It only makes this noise when i am gently accelerating, and sometimes on the decel. I hardly coast in neutral though. I was actually getting online tonight to research this a bit. I dont know if it is normal either. I had the noisy dif (spyder gear droaning when turning) and did the TSB at 76k to fix that. This however did not change the final drive whine. 2004 Jetta.

Wow, that's the sound exactly! I think my sound began at 65,000 or 66,000 miles. It appears to be just a normal meshing sound of the gear teeth, I think, and I guess began after the gears broke in. My take is that this noise is normal. I have heard similar sounds in other cars as well I thimk. What is odd is that one day I just noticed it and I know it was not present previously.

I did read up on the overhaul procedure for these transaxles and there are several shim adjustments and that if they are off a little, the transaxle can be "noisy" and my guess is that this is just a normal change in tolerances.

Thanks.

--Nate