Manual Gearbox' and Transfer Case oils after 13 years

[Allworth]

I was changing oils today for transfer box and manual gearbox, and got shocked of the oil condition, especially of the gearbox. My car has 13 years and 119k miles on the clock.
Intentionally it was purely preventative reasons, but I was surprised how smooth gearbox works now; kicking gone, shifts significantly easier.
Pics of oils attached:
In fact oil is that old it even has bubble formations.

[SharpAndCunning]

Not sure if I'm the only one, but I can't see the photo's.

My car has 74k miles on it, but It's a 2014 so I should probably be replacing these fluids too.

[Allworth]

Originally Posted by SharpAndCunning

Not sure if I'm the only one, but I can't see the photo's.

My car has 74k miles on it, but It's a 2014 so I should probably be replacing these fluids too.

I have tried incognito mode and photos seems to be working.
I have made 1 minute videos of the oil condition.

Gearbox:

Transfer Case:

[wheela]

Thanks for posting this. I have a 2015 X1 35i, and I replaced the transmission fluid last year at 61.5k miles, and had my rear diff fluid replaced 2 years ago at 57k miles, but the diff was only because they were in there replacing a couple leaky seals. I knew transmission fluid should be kept on top of, but I didn't realize transfer case and diffs fluids went bad at such a rate, but these pictures (which I can see, but the way) leave an impression. After seeing this, I'll be sure to get my transfer case and front diff fluids replaced this spring at my next oil change. Obviously my fluids have roughly half the life and miles as those on your pics, but I plan on keeping this car indefinitely, and substantially increasing its power level, so I want to keep them nice and fresh!

Then around 100k, I'll probably replace all of them again (transmission, transfer case, and both diffs), and then maybe stick to around a 50k interval going forward.

[Allworth]

Originally Posted by wheela

Thanks for posting this. I have a 2015 X1 35i, and I replaced the transmission fluid last year at 61.5k miles, and had my rear diff fluid replaced 2 years ago at 57k miles, but the diff was only because they were in there replacing a couple leaky seals. I knew transmission fluid should be kept on top of, but I didn't realize transfer case and diffs fluids went bad at such a rate, but these pictures (which I can see, but the way) leave an impression. After seeing this, I'll be sure to get my transfer case and front diff fluids replaced this spring at my next oil change. Obviously my fluids have roughly half the life and miles as those on your pics, but I plan on keeping this car indefinitely, and substantially increasing its power level, so I want to keep them nice and fresh!

Then around 100k, I'll probably replace all of them again (transmission, transfer case, and both diffs), and then maybe stick to around a 50k interval going forward.

Some people reported that front differential fluid is usually less contaminated, but is quite simple job when you have car lifted up, comparing to transfer case that needs removing bracket which can be a bit tricky, but changing oil is much easier than replacing transfer case itself when it starts to malfunction.
Manual Gearbox oil replacement is easier and perhaps cheaper then engine oil replacement, thought a lot of people avoid it, also after engine oil replacement feeling that engine is working better is often placebo, whereas gearbox oil replacement benefits I can feel clear.

Is your car xdrive? (as transfer case only exists on xdrive)

[wheela]

Originally Posted by Allworth

Some people reported that front differential fluid is usually less contaminated, but is quite simple job when you have car lifted up, comparing to transfer case that needs removing bracket which can be a bit tricky, but changing oil is much easier than replacing transfer case itself when it starts to malfunction.
Manual Gearbox oil replacement is easier and perhaps cheaper then engine oil replacement, thought a lot of people avoid it, also after engine oil replacement feeling that engine is working better is often placebo, whereas gearbox oil replacement benefits I can feel clear.

Is your car xdrive? (as transfer case only exists on xdrive)

Yep, x-drive it is.

[Gamb1t]

All the oils can be done with a good lift. Transfer case is the trickiest and you'd have to use BMW's angel tears fluid. If you do a search, there is a good write up with photos for all fluid changes.

[Allworth]

This is official oil specification from ISTA for MANUAL Gearbox
Obviously it is MTF LT-3 for most vehicles.

[maxwmiller]

Nice work Allworth, there's few things more lovely than the smell of teenage diff fluid.

Most already know by now, but ZF (the OE manufacturer of most BMW transmissions) says gearbox service is necessary every 60-80,000 miles. Do not buy BMW's "lifetime fluid" claim, just drop the pan and replace the fluid every four to five years. It is a very cheap way to ensure a smooth, reliable transmission.

[05X3lover]

Originally Posted by maxwmiller

Nice work Allworth, there's few things more lovely than the smell of teenage diff fluid.

Most already know by know, but ZF (the OE manufacturer of most BMW transmissions) says gearbox service is necessary every 60-80,000 miles. Do not buy BMW's "lifetime fluid" claim, just drop the pan and replace the fluid every four to five years. It is a very cheap way to ensure a smooth, reliable transmission.

Yep. We had our 2017 done all already, as well as we always had the fluids changed in our '05 X3 when we had it. So important to the longevity of the vehicle. BMW's BS 'lifetime' fluid claim is a great disservice to anyone buying their cars. I've seen other manufacturers are pulling this crap as well..

[Allworth]

Originally Posted by 05X3lover

Yep. We had our 2017 done all already, as well as we always had the fluids changed in our '05 X3 when we had it. So important to the longevity of the vehicle. BMW's BS 'lifetime' fluid claim is a great disservice to anyone buying their cars. I've seen other manufacturers are pulling this crap as well..

True. Could be some people put different meaning into 'lifetime', but I am now strongly convinced in a positive response after fluid change, especially when mileage is as big as 120k and car is almost 13 years old. This also applies to hydraulic steering fluid that I've just recharged. Steering is now smoother and lighter.
Power steering system gulped whole 1L bottle so I can not make a comparison of old/new fluids easily, but I do have samples of BLACK slime