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vtraudt
12-13-2010, 05:17 AM
My trans is slipping from 2nd on. I tried the fill up procedure with right trans temp twice. To rule out low trans fluid as a cause, I would like to 'overfill'.
We have a nice cold day today, so I could get the engine running, shift through gears (10 sec each), raise car, get fill plug out, insert the fill hose, and pump ATF in until if overflows. All with a much lower (say 10-20 deg C rather than 35-45 deg C as recommended). I assume this would cause a higher fill level.

What if any are the risks involved in do so?
If it solves my problem, I would know that it has to do with the ATF level (or pickup tube or filter or else).
If it does NOT impact the problem, I would just get the car to 35 deg C and take the fill plug out and let the extra fluid drain.

Input, please!

bigblue
12-13-2010, 06:29 AM
Since when do you fill the auto tranny till it comes out the fill hole?

vtraudt
12-13-2010, 06:42 AM
Here is in short words the procedure according to Bentley (posted by fellow forum member). Monitor fluid temp with VAGcom to be in the 35-45 deg range:
To flush you will need to use the SWAG method or a vagcom, Pull fill, then drain plug, pull pan, clean magnetic cubes, swap filter. Install drain plug, and pump oil in through fill plug till overflowing. Start car, pump till flooding. Run through all posistions for 30 sec each, fill till overflowing. Repeat for roughly 15 mins (check vagcom to see trans temp) install fill plug, turn off car.

FNK
12-13-2010, 07:00 AM
Shifting true all the gear is pointless since the car will just lock the first one until you drive.
Using a VAGCOM, fill the transmission because the fluid hit 40 Celsius, overfill.
Fill it and let it warm until the fluid reach 40~45 Celcius, perfect.
more, the ATF will keep on increasing in volume and will underfill.

I doubt it's fluid if it slip that bad, it's a possibility, but a rebuild might be needed (wornout components).

bigblue
12-13-2010, 07:06 AM
Probably Torque convertor... an when I had my transmission flushed at the dealer they actually run it through gears on rollers.

vtraudt
12-13-2010, 10:18 AM
Shifting true all the gear is pointless since the car will just lock the first one until you drive.

==> I am sure it makes sense to shift, since it allows the fluid to fill all the valves, etc.


Using a VAGCOM, fill the transmission because the fluid hit 40 Celsius, overfill.
Fill it and let it warm until the fluid reach 40~45 Celcius, perfect.
more, the ATF will keep on increasing in volume and will underfill.

==> Done that twice, so should have the right fill (unless something else is preventing the fluid to fill; I installed a new radiator (which has the trans cooling integrated) and had cleaned the hoses to/from the trans)


I doubt it's fluid if it slip that bad, it's a possibility, but a rebuild might be needed (wornout components).

==> I sure hope not. Paid good money for the trans.

But I did NOT drop the pan and checked/cleaned/replaced the filter.

vtraudt
12-13-2010, 10:19 AM
Probably Torque convertor... an when I had my transmission flushed at the dealer they actually run it through gears on rollers.

But its pulling hard in 1st and reverse (spin wheels on gravel, go up steep driveway). Wouldn't a bad toque converter show slip there, too?
It goes from pulling to nothing when the upshift occurs.

FNK
12-14-2010, 06:48 AM
If you can feel your transmission shift, but then "spin out", you have problems. This means your clutch pack or shift band has burned out. It's not good news, because this does mean an overhaul. Inside the transmission are several clutch packs and bands. There are also several more sprag, or one way clutches. The clutch packs consist of pistons that apply pressure against a "pack of friction and steel plates" that drive a sun gear, planet gear, or ring gear. (Planetary gear sets are the basis of automatic transmissions). A sure way to tell is to remove the dipstick, or drop the transmission pan and smell and inspect the fluid. If it is burnt smelling, dark and discolored, it's not a good sign.
Source : http://www.ehow.com/how_5357959_diagnose-automatic-transmission-problems.html

This happened to me on a previous car, a piston housing was cracked and losing pressure, causing the trans to slip in higher gears.

vtraudt
12-14-2010, 07:28 AM
I haven't dropped the pan yet (parts on order, expected today). But fluid (spilled plenty) looks and feels clean, red, not dark, no burnt smell.
I have already asked my transmission shop if they drop the pan when doing a flush; in which case I will probably trailer the car to them for
- drop pan, clean, new filter
- flush, refill
- further diagnosis

Someone told me that the trans works to some extend even if the connectors (2 round plugs) are disconnected?

Is that the case?

If so, would this help with troubleshooting? If it works (say: 5th gear or whatever it uses without input from controller), it would point towards electrical (valve body, solenoids, TCM, ECM, sensors). If not (but supposed to), mechanical transmission issues (torque converter, filter, fluid, clutches, etc.)?

FNK
12-14-2010, 08:56 AM
Red ATF fluid?
While giving them a call, ask what they used.

Normaly, ZF transmissions are filled golden ATF

Only the second gear slip?
Have you scanned your Trans with Vagcom?

somebody5788
12-14-2010, 09:34 AM
If it had red fluid that right there could be your problem. Supposed to have Volkswagen synthetic ATF in it which is almost water clear with a golden tint like FNK mentioned

Scotty@Advanced
12-14-2010, 09:40 AM
My trans is slipping from 2nd on. I tried the fill up procedure with right trans temp twice. To rule out low trans fluid as a cause, I would like to 'overfill'.
We have a nice cold day today, so I could get the engine running, shift through gears (10 sec each), raise car, get fill plug out, insert the fill hose, and pump ATF in until if overflows. All with a much lower (say 10-20 deg C rather than 35-45 deg C as recommended). I assume this would cause a higher fill level.

What if any are the risks involved in do so?
If it solves my problem, I would know that it has to do with the ATF level (or pickup tube or filter or else).
If it does NOT impact the problem, I would just get the car to 35 deg C and take the fill plug out and let the extra fluid drain.

Input, please!

Overfilling an automatic is a Very bad idea, in fact its pretty retarded to do it intentionally.

If overfilled the fluid can foam due to the rotating internals whipping it up, then the pump sucks in foamed fluid and starts to cavitate making noise and destroying the pump, while not putting out the proper pressure which means burnt up clutches.

vtraudt
12-14-2010, 10:14 AM
trans was used, no way of telling what ATF is in.
I read up on VAG (I think Pentosil, a no name German manufacturer who makes it for VAG) ATF vs. alternatives. Mobil 1 synthetic (and others) have been used successfully (see lots of posts on various forums).

Mobil 1 Synthetic ATF is also suitable for use in vehicles that specify the following fluid requirements:

Audi G 052 025-A2, G 052 162-A1
BMW LA2634
Esso LT 71141

And fluids can be mixed (has to be, because it is never possible to drain a trans completely (unless taken apart)).

But I don't want to start a discussion here.

IF my trans shop will do a flush, I will ask them to put in VAG in (more out of desperation than technical belief).
Initial fill is 9.0 liter (9.5 quart) of ESSO EGL 71141 (Bentely), 2-3 quart for filter change.