Hey guys, I have been having a vibration in the floor since I pulled my car out of storage.

Its a 2000 2.7t 6 speed

I know its not the wheels because I have access to a hunter roadforce balancer and a snap on laser balancer (I work in the tire industry). I have three sets of wheels that I balance and tire match using those two machines. They all run true with no runout or shimmy whatsoever. They are also hubcentric and are torqued to perfection! []

Now that is out of the way, maybe you guys can help me.

This vibration happens between 80-130km/h, though I have felt some shuddering at lower speeds that dissapear quite quickly. On the highway though it feels like a rollercoater because it comes and it goes, even at the same speed. I feel it through the floor, but not through the backseat as much as the front seat. It feels cental and to the front. The vibrations are not related to the rpms, they happen when accelerating, decelerating, coasting in neutral with clutch in and out. When going over bumps and dips it does feel as though it lessens for a bit but that could be me. I feel it the worst in the gas pedal which is confusing to me, the clutch and brake pedal are motionless. It doesnt change when taking corners or going uphill or down.

I have the oppurtunity to check the front end suspension and they are all solid wtih no movement. There is also no squeeks, creaks, knocks or any other noise. The H&R coils are not leaking and feel very solid while cornering. The CV boots are not torn and make no clicking noise. The driveshafts are tight and exhibit no play in them. There is no visible fluid leaking from the engine mounts.

This weekend I will get some hoist time at my retail tire and alignment shop so I will be checking motor mounts, tranny mounts, center support bearing, propshaft CV's, and whatever else you guys think I should check.

Some questions
I noticed that the snub mount (ECS) is a little loose around the **** attached to the motor, could this cause anything like I mentioned?
What is the proper way of checking engine and tranny mounts?
I havent replaced my fuel filter in 60,000 kms, could this be a fuel related proplem?
Could driveshafts cause this even though there are no tell tale signs they are worn/wearing out?
Would upper strut mounts cause this kind of problem?


Any help would be greatly appreciated. Though I dont hit the highway a tonne, when I go on it I dont want to feel like my buddies Civic on coilover sleeves.

Thanks In Advance

 

Bud, we are just having the same conversation over here:
https://www.audiforums.com/forum/sho...d.php?t=170665

Sure there is some talk about simply balancing or doing an alignment but there are some good ideas where to start looking if that has been checked already.

check that link out, add your opinion and maybe we can all find out what is haunting our cars.

 

I personally think it is a design issue that leads to the shopping cart wheel issue. I've had the same issue for the past 4 years. Nothing fixes it. Let me know if you find out the issue.

Bob