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Transmission oil change

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#1 ·
Hi, there is much discussion on here about lifetime transmission oil, (remembering the Diff as well). Many believe that lifetime is a misnomer, I read a small but interesting article that said if you change the transmission oil do it at around 60K miles (KM equivalent). If you leave it much later then the oil becomes thicker and the wear profile of the transmission in a sense accommodates this ageing of the oil. So much so that if you wait till, say 100K to change the oil, then it is so much thinner when new and it is this that can lead to problems with the transmission. The moral being change well before say 100k and after this leave it as it may cause more issues and offer no tangible benefit.
 
#2 ·
Well I'm in trouble then because my gearbox pan started leaking a few days ago and now I "have to" change the pan and the oil . I doubt it makes much of a difference , because unless you change the oil a half a dozen times the vast majority of the oil remains in the gearbox when you drain it from the drain point
 
#3 ·
The whole point is for people to make decisions for themselves as to whether or not you should change the oil. People can show cars with 200k miles without an transmission oil change, then another with say 50K with a leaking transmission pan, but in these cases BMW still reuse the old oil and top up that what was lost to the leak...... peace of mind always comes at a price!!!! I for myself have yet to decide as I want to keep this car for a long time !!!
With well petrol and oil as a diminishing resource, and going at an ever faster rate, in 2025 the consumption of oil will exceed that which is available, upto that point petrol and oil will continue to rise and rise. We should only look at the current issues with unrest in the Middle East to see what is a forecast for the near future...............for my part I have found the car that I am content to take into the future......
Mute point anyone converted a 6 series to LPG ???????
 
#4 ·
Lifetime transmission fluid is one of those "black magic" subjects. Very difficult to get a straight answer since it is hard to prove the different trains of thought.

My understanding of this issue is the same as the OP. Changing tranny oil on a car with high mileage can result in accelerated transmission failure. A couple of BMW techs have also told me this. The techs told me that the clutch packs in auto transmissions have friction material on each disc. As the friction material wears off, it is suspended in the oil. Oil with suspended friction material helps the clutch packs continue to work even though the discs now have less friction material on them.

Change to new "slippery" oil and the worn clutch packs will wear out at an accelerated rate compared to just leaving in the old oil.

The techs also said you still should change out the oil at 100K miles because by that point the fluid is contaminated to where it does more harm than good.

There is no way I can verify this info but it sounds reasonable to me. Luckily I have a 6 MT so I don't have to worry about the "to change or not to change" dilemma.

Don't worry about oil shortages, we've got you covered here in Canada with the tar sands. ;)
 
#5 · (Edited)
I imagine I'll have a newer M6 before worrying about the tranny fluid.

Don't worry about oil shortages, we've got you covered here in Canada with the tar sands. ;)
Yeah, We are starting to frackture here in Texas. Between Texas and the upper mid states, we have twice the oil of all of the Middle Eastern countries combined. Something about some left footed, horny toads matting habits prevents us from drilling in the upper mid states. Want to see some pissed off tree huggers and horny toads...wait till the middle eastern supply runs dry.:rofl::rofl:

There will be some technology advances, whether real or imagined that make drilling for oil environmentally safe. Therefore the politicians can please both sides. Then we get to charge $110 a barrel. And what would become of one of our dearest friends, OPEC.
 
#6 ·
petrol prices

I imagine I'll have a newer M6 before worrying about the tranny fluid.

Yeah, We are starting to frackture here in Texas. Between Texas and the upper mid states, we have twice the oil of all of the Middle Eastern countries combined. Something about some left footed, horny toads matting habits prevents us from drilling in the upper mid states. Want to see some pissed off tree huggers and horny toads...wait till the middle eastern supply runs dry.:rofl::rofl:

There will be some technology advances, whether real or imagined that make drilling for oil environmentally safe. Therefore the politicians can please both sides. Then we get to charge $110 a barrel. And what would become of one of our dearest friends, OPEC.
The issue in the UK is that we pay nearly $9 per gallon of petrol and rising, (even taking into account the Imperial gallon to the American gallon which is slightly less)
So you can see we have to really love our 6 Series and at times get the 25mpg and 30+mpg when doing 80mph on the motorway and 18 mpg when really having some fun........which is the best lol
 
#7 ·
The issue in the UK is that we pay nearly $9 per gallon of petrol and rising, (even taking into account the Imperial gallon to the American gallon which is slightly less)
So you can see we have to really love our 6 Series and at times get the 25mpg and 30+mpg when doing 80mph on the motorway and 18 mpg when really having some fun........which is the best lol
+1 here in ireland same about $9 a gallon
 
#9 ·
Gas prices are frustrating here in the states but i always say to myself i had the option to buy a hybrid but i chose a 6 as well as a LS400 and a Rover so i shouldnt really complain outloud about it. im part of the problem lol Typical American as my Canadian cousins would say..
 
#12 ·
I will change my pan and oil when the time comes. I did it with my 7 series and didnt regret it. I changed mine at 150,000 KM.

I couldnt believe the cost of the oil! I think I spent $175 on the oil alone. The guy at the dealership calls it "liquid gold"!! Its under lock and key at the dealership!
As for the filter, when I realized that BMW uses a paper filter, not a chain or other type, it leads me to believe that there is no way fluid and a paper filter can last the lifetime of the vehicle.... maybe the lifespan of when you actually own the car!.

Im only at 50,000 right now, but when I get there, if I still own the car, I will definitely change it.
"
 
#13 ·
I will change my pan and oil when the time comes. I did it with my 7 series and didnt regret it. I changed mine at 150,000 KM.

I couldnt believe the cost of the oil! I think I spent $175 on the oil alone. The guy at the dealership calls it "liquid gold"!! Its under lock and key at the dealership!
As for the filter, when I realized that BMW uses a paper filter, not a chain or other type, it leads me to believe that there is no way fluid and a paper filter can last the lifetime of the vehicle.... maybe the lifespan of when you actually own the car!.

Im only at 50,000 right now, but when I get there, if I still own the car, I will definitely change it.
"
I have 6ltrs of the oil (which they decanted out of a 20 gallon barrel) and paid nearly £180 and £200+ for the transmission pan and the mechtranic sleeve, now that is the dealer steal of the year, and guess what they sit in my garage because I sold my 6 before I did the work, I know it will all fit other BMW models but not sure which ones! I was told by a dealer parts department that they have transmission pans cracking on a range of cars...........
 
#14 ·
Just drop mine at 50K miles. Had the dealer do it and it didn't cost me anything realy. :) How you may ask. Well, I have a BMW credit card that I use a lot, and I've racked up so many points that you can actually convert to use at the dealership. So I use some points to pay for my service charge.
 
#15 ·
I hope some one can help me with my next problem:
I changed the sealing of the carterpan and drained the transmission fluid.
But now I don't now where to fill the transmission fluid.

I was hoping someone can help me with a picture or general section of the engine where to look.

Thanks in advance.
 
#16 · (Edited)
Hi! there is a golden rule never drain until you have opened the fill plug!!!! Otherwise you cannot get the fluid back in! Having said this there is a thread on how to fill, it needs a pump and you have to follow a set procedure it is not just a matter of poring it back in !!!! The fill plug is just up from the exhaust pipe on the drivers side you cannot miss it, it can be a pig to release and even tighten up later!!!! If you get a copy of the TIS it is easy to find!!!!!
I trust we are talking auto box here??? If it is the manual transmission then it is fairly straight forward in terms of filling....
 
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