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Discussion Starter · #1 ·
I have a 2003 4Mo wagon with 30V 2.8L AT, about 205k miles. For over a year it has had a slight shudder in 1st gear at the beginning of acceleration under medium or greater throttle. It only does if from idle to maybe 2-3000 rpm. Light throttle, no shudder.

Now I notice it a little in 2nd gear as well. So, on take-off most of the time I get light shudder/vibration in 1st, goes away as rpm increases, then into 2nd and light shudder again, goes away as rpm increases, and then all higher gears normal.

I just changed tranny fluid & filter again (was done at 100k also), and no change in characteristic. The sound is not metallic, and doesn't feel like any slippage. I'm not terribly worried as it has been going on a long time, but it sure would be nice to know what it is & fix if possible (practical).

I changed the motor & tranny mounts about a year ago, and no change there also. Have not replaced the front snubber yet, waiting to add this to the next front clip removal job.
 

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Being yours is the 4mo it could be the drive shaft components and not the transmission. It is hard to diagnose a shudder so to speak as the first thought always goes to it being the transmission but at times it is not. Not sure how to can go about figuring it out, just wanted to throw that out there for thought.
TomK
 

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Check TCM for fault codes. Perhaps there is some slippage. ATF fluid pressure might be low and not keeping the clutches or brake packs engaged, especially when the torque is highest and pump output low.
 

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Discussion Starter · #5 ·
I don't really think it is the tranny either, it seems sort of like the sound/vibration comes from the rear. The driveshaft does seem like a likely culprit. Maybe torque is causing the engine/tranny to move more than it should, causing extra driveshaft flex. I need to get that front snubber replaced.

No fault codes.

I have only replaced 1 axle, Rt front. (and it turned out to be not bad,)
 

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I expect it is either the center driveshaft support bearing or one of the center driveshaft CV joints. I am having the same issue and it feels much like a bad CV, but from the back of the car. Worse when turning, worse with more throttle, but still noticeable when going straight and under throttle. Rear CVs look fine, but I will have to drop the center heat shield to check the center bearing and CV joints.
Front CVs are nearly new and in fine shape.
 

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Discussion Starter · #8 ·
I replaced the driveshaft yesterday with a shaft out of a 2002 W8 4Motion sedan, it looks like all B5 & B5.5 Passats use the same part number, regardless of engine or sedan/wagon, 3B0521101R. When I got mint out, if found the center U-joint had a little play also. The hanger bearing has sort of a heavy flexible rubber boot suspending it, mine had plenty of stress/age fractures, visible if you stretch it out a little.

Rust Auto part Metal


The junkyard shaft was in better shape, but still pretty soft on the hanger rubber. So, I filled in one side with RTV rubber & let dry for a day. Installed pretty easily and I took the car for a drive today. Works great!! No more noise on takeoff! Apparently the driveshaft was flopping a bit and rubbing against the heat shield below. This shaft is quite a bit tighter too, so including RTV total repair cost about $25.
 

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Discussion Starter · #10 ·
Not that I can tell, heck I can't even feel the looseness that I felt when it was mounted in the car. Since it spends its' whole life in 1 position with negligible flex, I imagine pulling it out and redistributing grease for the first time is enough to hide the looseness.
 
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