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Discussion Starter #1
I had had some concerns about some thumping in my tranny when going from P to D to R with a very slight delay in engagement, there also was a vibration at idle in D and R. I had no driving issues just at idle. The car has 47,000 it's a 99 AEB with GIAC ECU and Tranny chip.

So I beared down and did a full fluid change, filter and cleaned the pan.
The pan looked decent no big metal shavings on the magnets, just a pulverized grease looking accumulation aprox 1/8 of an inch deep, the fluid was black and did not smell cooked, the bottom of the pan had a little residue, but nothing one wipe of a rag would not remove.

I drained aprox 4 quarts from the pan, dropped the pan another say .50 of a quart came out, pulled the filter another .25 quart came out, I reinstalled the pan and waited for the filter to come in.


The tranny drained over 2 nights, I pulled the pan again and found another
.50 of a quart from the extended drain/drip.

I installed the new filter, pan, and gasket. I poured in three quarts and started it, I brought it up to aprox 100f and poured in 2.5 more, the temp went to 125f by now so I figured it was over temp to get an accurate fill rating.

The car engaged better after this, so I took it for a test drive, nice!!
On my second test drive everything was perfect, I was at a light with my foot on the brake and it skipped/slipped for a split second, it never did this prior. It scared the s$%T out of me, so I drove it home, on one final stop b efore my house it skipped on a downshift, real quick.

It acts perfectly under load and shifting, and since it has not skipped/slipped since, but I am concerned.

I also have noticed at idle in D and R with my foot on the brake it vibrates aagain and goes away with acceleration.

Do you think I need more fluid? I removed about 5 quarts and put back in 5.25- 5.50 with a 2 night extended drain?

Would you guys worry about 2 isolated momentary slips, or try and fill it some more?

Any help would be appreciated


TJ
 

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give it a few miles... very likely was air in the valve body. 'Low fluid' causes slip, so a bubble would also. I'd do 30-40 miles easily using all the gears you can, and then check the level quick... if it does it after that, then you may want to have it looked at, but I'd bet it will settle itself out.
 

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Discussion Starter #3
Thanks, I just need a little of encouragement :) The real pisser is the vibration at idle in D and R, it's pretty strong, but immediately goes away with the slightest throttle blip, I changed motor mounts(V6 part) and tranny mounts before the fluid change, in hopes to get rid of it.

I am no auto tranny guru, so I was wondering if it was possible that a low fluid condition could cause the TC to vibrate at idle, or does the tranny regulate the ATF to a mean pressure regardless of RPM?

Have you guys ever heard of a vribration problem at idle in D or R in another auto, and was it a serious problem? :nervous:



TJ
 

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I've had that same vibration since day 1. It's exactly as you describe - slight blip in RPMs, and it's gone. I've got an 03 Tip with 29,999.8 mi on it (as of this morning).
 

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I had vibes in the cabin while in drive at idle since day one in my 01 4Mo. It's wasn't so much a matter that the engine/tranny were vibrating too much, but that EVERY internal surface happened to resonate at THAT frequency.

Day two of ownership I used the VAG-COM and changes the idle speed. Played with a little higher, and a little lower, and found a sweet spot at about 680 RPM. Still within the spec for the 4Mo (for some reason the 4Mo idle is allowed to go lower than a normal V6 ?) but it didn't cause any of the resonance of the cabin surfaces, so it was WAY better.
 

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I too have had a vibration at stop. I asked the dealer and mechanic a couple of weeks after I bought it and they said it was normal. What were the steps used to adjust the idle with the VAG-COM?
 

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Check to make sure that the heat shields are not loose and touching the exhaust, or maybe the motor mounts are too stiff since they are for the V6. Other than that I am not sure what to tell you.
 

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Black-Magic said:
I too have had a vibration at stop. I asked the dealer and mechanic a couple of weeks after I bought it and they said it was normal. What were the steps used to adjust the idle with the VAG-COM?
Black-Magic... here's a PDF of the Idle speed checking and adjustment out of the Bentley for the V6 (ATQ). The only thing different will be the RMP range if you have a different engine (assuming you have a TIP).

IDLE SPEED ADJUSTMENT
 

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What you are describing is exactly what I had going on and it was the motor mounts. It wasn't on my Passat but another VW that I owned. You said you changed the mounts and I'm thinking ditto with Black-Magic.

However, in reference to that slip, I had an experience just like that on my '98 1.8T Tip :b5: . Scared me especially with another car sitting right in front of me. I thought I hit the gas. So it can be caused by low fluid in the tranny? Time to check that out.
 

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I tried your link (pass-variant) for the idle adjustment and it said that it was not available. I should be getting my new service manual this week so I will try to find it in there. Thanks though!
 

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My car also had vibration at idle in D. What fixed it was not related to the tranny, so this may not help you..

1. Clean the shi*t out of the throttle body
2. Raise the idle speed with a vagcom. (normal is ~750rpm, I raised it to ~850)

My car is so smooth even while idling, I can hardly tell its on.

one more thing.. did you use a lint-free cloth to clean the pan? I've studied transmissions extensively and there is a common problem known as 'red rag disease' that can trash a tranny. It happens when old rags are used during overhauls or fluid changes and the lint gets into fluid passages causing slippage or other problems. The filter would probably catch this during a simple fluid change, but be careful!
 

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Tj
I had the same problem a few weeks ago. Exactly what you are going threw i went thru, i was even more scared cause i'm using the Redline D4 atf.. So i was shitting bricks. But as time went on, the car smoothed itself out. :lol: I notice now that the car makes a weird noise when in P and also in R. But thats about it. it sounds like a little rumbling going on in the tranny. But once your in a different gear the noise is gone. Maybe this week if i have time i will check the fluid level. Have fun guys.. BeCareful

Nick
P.S : its about 3500 miles on the REDLINE fluid and all i can say is :thumbup:
 
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