03 325i auto Transmission shudder at low speeds in between gear changes 2-3

[CC325i]

2003 325i E46
Automatic steptronic
4door
M56 motor
147k miles


I have searched online and have found people with a similar problem but under different circumstances and with no clear information/answer.

I have noticed in the past few days when I accelerate slowly as you would in traffic I feel a shudder type of vibration in the transmission usually from 2nd to 3rd gear. Only happens under light acceleration and last only 2-3 seconds

also owning manual gearbox BMW's I have felt a manual clutch shudder before and that's what it feels like on my automatic so I fear that the clutch band/brake band inside of the transmission for the planetary gears is vibrating/shuddering against the 2 surfaces.

Could anyone shed some light on this or confirm what I think is the problem? I already feel that a replacement transmission is in the near future even tho the car drives very well still but anything out of the ordinary little or small I cant sleep at night.

**This car has sat for a year unused, I have changed the trans fluid and filter since the problem appeared. fluid was clean red

[hakentt]

worn U joint will do that.

[Divemasterdave]

Any luck diagnosing/fixing the problem? Mine is doing the exact same thing.

[djb2]

Have you tried freshening your fluid?

Use the correct fluid, with a LT71141 rating. Valvoline has a full synthetic MaxLife fluid with this rating that might find at Walmart in a gallon container for under $20.
The original factory fluid was olive green, which quickly looks black, so don't be surprised if that what pours out. Most multi-spec fluids, including the Valvoline, are dyed red so a red fluid indicates that it has been changed. Hopefully they changed it with a compatible fluid.

If you drop the pan to inspect the magnets you'll want to have a fresh gasket ready. The factory gasket was a thin green "paper" type. Aftermarket ones are sometimes thicker rubber gaskets. Rubber gaskets seal better against imperfect surfaces. Fiber gaskets last longer and seep less if they form a good initial seal.

The filter is large and unlikely to be clogged, and some aftermarket filters cause problems with suction, so changing it isn't a top priority. If you open it up and the filter isn't a factory 'ZF' branded metal type, plan on changing it the next time.

Once the pan is down, it's worth the time to remove the six exposed solenoid valves. (Skip the seventh hidden under the valve body.) The valves slightly magnetized, so wipe them down to see if they are covered with metal powder. Three will have inlet screens -- check that they aren't clogged.

The 5HP19 transmission uses only clutches, not bands. The clutches are less prone to wear and require complete transmission disassembly to replace, so you should look everywhere else for a solution first. The valve body is a more likely culprit and is just a handful of screws to remove one you have the oil pan off. Swapping in a used one ($120 on eBay right now) or cleaning your current one is a reasonable step if the alternative is dropping the transmission.

[MarcoZandrini]

The first step is to have the engine computer (DME in BMWeze) and the tranny computer (EGS) scanned for codes. Next, you need to determine which brand of tranny is in the car. Bmw sourced automatic trannies from GM of France and from ZF, a German company. They are totally different trannies!! The GM tranny has a smooth, flat tranby fluid pan. The ZF tranny has a ribbed tranny fluid pan.

What's the maintenance history of the car and specifically the tranny? Lifetime fluids was a marketing ploy, not a maintenance philosophy!

[djb2]

The first step is to have the engine computer (DME in BMWeze) and the tranny computer (EGS) scanned for codes. Next, you need to determine which brand of tranny is in the car. Bmw sourced automatic trannies from GM of France and from ZF, a German company. They are totally different trannies!! The GM tranny has a smooth, flat tranby fluid pan. The ZF tranny has a ribbed tranny fluid pan.

What's the maintenance history of the car and specifically the tranny? Lifetime fluids was a marketing ploy, not a maintenance philosophy!

Oh, you are right -- if it's a GM transmission it's a completely different set of potential problems and fixes. With a MY2002 I was assuming that it was a ZF 5HP19 transmission that was just past the era of cracking reverse/D drums.