Transmission Whines When Cold??

[Skyking6976]

Was greeted in the Midwest by VERY cold morning temps the past couple of mornings and I guess it's the transmission that makes kind of a whine noise until it arms up...almost out of the blue on the temp gauge. For now the car sits outside so there's not much I can do about keeping it inside.

Is this normal or do I need to have someone take a look?

[George K]

Was greeted in the Midwest by VERY cold morning temps the past couple of mornings and I guess it's the transmission that makes kind of a whine noise until it arms up...almost out of the blue on the temp gauge. For now the car sits outside so there's not much I can do about keeping it inside.

Is this normal or do I need to have someone take a look?

I'm in Chicago, and drive mine all year long. I've never noticed this, even after it's been parked out on the coldest days.

[sgd98]

What type of transmission (manual, automatic, SMG) and how many miles?

I have a 6-speed manual transmission. My car sleeps in a garage and it probably never gets below 35 degrees F, but I don't recall ever hearing any whining from the transmission. The only temperature-related effect seems to be stiffer shifting when cold (which is not in the least bit unexpected).

Does anything other than temperature affect the sound? For instance, does it seem to change as you shift gears? Do you hear the noise in neutral? Does it rise and fall with engine RPM?

[Skyking6976]

I have a 2.5 automatic. Nope, once it warms up it seems fine. The whine noise stops. I've got 80,000 miles on it.

I bought the car from a Dodger Chrysler dealership in August, not BMW, so I'm still a little nervous about everything. If anyone knows a good BMW shop in the KC area it would be greatly appreciated. I'm thinking about having the radiator, brakes, oil and automatic transmission fluid replaced anyway. The dealership said they did an inspection, changed the oil, etc. but when I saw the condition of the air filter it really made me wonder what if anything they did on the "inspection".

I have to wonder when\if the transmission fluid has ever been changed or if it's low. Just very frustrating.

[sgd98]

I would definitely check the transmission fluid level as a first step. Then maybe bring it to a dealer or independent shop to get their opinion/diagnosis. (If there is truly something wrong, it may get more expensive the longer you wait.)

Regarding fluid replacement, that would be a good idea. Without any evidence to the contrary, I think you should assume that no fluid changes have been performed anytime recently (the transmission and differential, probably never). Even if the factory maintenance schedule has been followed religiously, the service intervals are still pretty long (there is a financial incentive for BMW to limit maintenance, since BMW covers maintenance for free the first few years). And who knows what the Dodge/Chrysler dealer inspection really consisted of. It could have just been a basic safety check.

The maintenance intervals I use:
automatic transmission (if I had one) fluid & filter: every 60k miles
manual transmission fluid: every 30k miles, Red Line MTL or Roayl Purple Synchromax
differential fluid: every 30k miles, Red Line 75W-90
brake fluid: flush and replace once per year, DOT 4 synthetic brake fluid
coolant: every 2 years, genuine BMW coolant
engine oil and filter: every 5k miles, 5W30 synthetic, Mobil 1, BMW or Valvoline
air filter: check at 15k miles, replace at least every 30k miles
spark plugs: replace every 60k miles
cabin air filter: replace every 15k to 30k miles
serpentine belts: replace every 60k miles with genuine BMW belts

The engine oil interval might be stretched out a bit more. The only real way to tell is with a used oil analysis, but I figure a good synthetic oil will certainly last at least 5k miles. In the past I used a 3000 mile interval, but I have recently convinced myself that is probably excessive. I do oil changes myself, rotate tires at the same time and check other things while I am at it (fluid levels, tire pressures, brake pad thickness).

On a related note, I am a subscriber to Mike Miller's "old school maintenance schedule." Mike is the technical editor for the BMW Car Club of America (bmwcca.org). He has a column in the monthly club magazine where he discusses maintenance and other matters. If you are not a member, I highly recommend joining (the magazine alone is worth it to me). My dealer gives me a discount on parts for being a member, so that offsets the cost of the club membership. And Mike will email you his maintenance schedule and answer your technical questions.

[studentofspeed]

Does it make a barely noticeable high pitched whistle? I've noticed mine does it as well. Pretty sure it's the AT as my neighbour has a 2.5 with the 5MT. It doesn't whine when cold, but my 3.0 AT does. Don't worry, it appears to be normal.

[dkl]

Check your transmission filter. My X5 (3.0i) was doing the same thing until I had the filter replaced. During the transmission service, my indy mechanic found that the filter was essentially sitting on the pan due to the faulty o-ring. It needed to build pressure for the filter to get "sucked" back up into position and the whine will disappeared (that's why the whine doesn't exist when warm...it only happens after sitting over-night out in the cold). With the new filter and o-ring, the filter should stay in place. It's a bad design, IMHO, as the only thing holding the filter in place is the o-ring.

BTW...You should replace it with an OEM filter as most aftermarket have an inferior o-ring design as my mechanic showed me the various aftermarket filters for comparison (he actually ordered a few various filters during my service just for comparison and I'm glad he did). No more whining after the fluid and filter replacement.

[Skyking6976]

Wow, thanks for the info all. I'm going to a local mechanic I've been referred to. The town I'm in has a population of just under 2,000 and 90% of the vehicles are good ole Chevys, Ford etc., the rest are Honda Civics. I'll definitely have the transmission filter changed with the OEM one. My boss has classic cars that are maintained by a weird dude but he's a good mechanic. Someone you have to stay with or he gets off task. Maybe he can do it with my supervision.

I'll keep y'all posted.

[dkl]

I just realized that the filter on your 2.5 may have a slightly different design from my 3.0i X5, in that it may have a couple of bolts holding it in place rather than just an o-ring as in my X5. So, the "loose" filter theory may not be your problem. In any case, 80k on the original fluid and filter is probably due for a change anyway (BMW is now recommending a fluid change at 100k on their "lifetime" fluid).

[Skyking6976]

Just thought I'd take a minute and update you on the transmission issue. I'm having my friend\mechanic change the oil, plugs, bleed the brakes and change the transmission fluid\filter\gasket. He just called and said the fluid was black and the filter was filthy. The car only has 80,000 miles and I'm not sure it would have made it 100,000 miles. The guy said it looked so bad he suggests I run the new fluid until my next oil change and change the transmission oil\filter again. Hum....

I could feel and hear it shift just fine except as I mentioned before when it was very cold ~30's.

[dkl]

Did the whine went away after the fluid changed? Also, how did your mechanic changed the fluid? Did he just drain it from the pan? The pan only contain about 30% of the fluids with the rest being in your torque converter.

[Skyking6976]

I had to wait until the was a cold morning and yes the wine is gone...go figure. There is still a little rattling sound around 2,000 RPM through the first 3 gears on the automatic transmission but it shifts smooth as silk.

We had to put the fluid in by running a hose from above the engine while the other one was under the car making sure the tube stayed in the fill hole. Kind of a hassle but I kept thinking about how much I was saving not going to a dealer or BMW shop.

[sgd98]

Glad to hear you got rid of the whine, and even better that it did not cost you much!

Regarding the rattle at 2000 RPM, you might search for "DISA" valve. I don't have any direct experience with this and haven't had any trouble with my DISA valve, but your description may point in that direction.

[dkl]

A faulty "DISA" valve should rattle at all RPMs, not just 2k. Needless to say, I've been through this "DISA" valve replacement as well. Not too difficult of a job for the DIY'er...just a couple of bolts holding it in place. The part is a couple hundred bucks, though

[dav781]

hello, maybe you can point me in the right direction.. I have the same car, 6 speed manual, new fluid (checked levels twice)
when cold, it whines /gurgles between 15 and 40 mph, the whine tone rises/lowers with rpm, whether in gear or neutral, it still whines if moving, quiet when car is still...
sound comes from transmission (not transaxle) :-)
any clues? car has 140k miles but well kept

David