Odd increase in vibration?

[rwthomas1]

Hello all,
Got a bit of a headscratcher here. Over the last 3 weeks or so, my 03 Jetta has started to vibrate more. Well, I can feel and see it more, in the wheel, seat of the pants, etc. Louder too when accelerating. I changed engine mounts, i think, sometime in the past year or so. I'm wondering if an engine mount failed, and is transmitting more vibration than normal? Vibration is engine speed dependent, high frequency and not speed based. Never heard of a mount failing that quickly, but I assume it's possible. What say the crowd?
Thanks, RT

 

[STDOUBT]

I would think a new mount could only fail if the fasteners weren't properly torqued down, and got beat up because of it.
Also when you mounted them, did you go through the little alignment instructions like in the Bently?
There's a measurement on each end of a gap for the 'front' engine mount, and a line-up you do for the transmission side.

 

[Duke_962]

Does it shake/vibrate worse under hard acceleration and then go away as soon as you let off the pedal? If so it’s your axles. Flat road 3/4 gear at 2000rpm steady pedal and then mash it. If the vibration gets worse then back off and see if it goes away. If so it’s driveline mostly axles. If you can put the car in the air ( or jack it up) put it in neutral and hold the inner cv axle cup in one hand. Moved the wheel and see if there is a lot of slop in the wheel before the axle moves. If so it’s most likely play in the axle joints. Had this issue in mine at 280k. Replaced both joints and it was smooth as new. Hope this helps update if you can and I will offers ideas based on what you say. Good luck.

 

[rwthomas1]

The mounts are aligned correctly. The axles are brand new Raxles. The vibration is not speed dependent. I have just noticed, for example, that coming to a stop there is more vibration transmitted to the steering wheel and dashboard. Clutch in, or out, rolling or not. There appears to be more body noise or rumble, as if more vibration is being transmitted to the vehicle structure, than before. Since this came on kinda quickly, over a period if weeks, I suspect a mount has failed.
RT

 

[Duke_962]

Are they factory stock mounts? Or aftermarket

 

[rwthomas1]

Are they factory stock mounts? Or aftermarket

Aftermarket stock mounts from IDParts. Third set of mounts. Last set came out and leaked oil so they were dead. My experience with VW diesels is to change mounts every 100K. Helps with NVH.
RT

 

[JDSwan87]

Check your axle nuts

 

[Duke_962]

Sounds like the mounts then. Maybe they had a batch of different Durometer rubber in a run. I try to stick to factory stuff since I have been burned on some aftermarket stuff but I don’t think Id parts are that bad kinda surprising. Only thing i can add is how old is the flywheel. I have seen some start to shift out of balance and go out of balance but this is normally pretty pronounced and only way to check is to pull the trans. The bolt holes will be off center on the dual mass flywheel (assuming you have a stock setup). Just another idea for you to check. Also check your harmonic balancer but when they fail it’s normally a game over situation. Good luck hope this helps