Transmission fluid - change or leave?

[Amsterdave]

My 2015 X5 35d has around 55,000 miles on it now and just came off its extended warranty with most major items (EGR, cat, control arms, air suspension bags) fixed or replaced while still under coverage, so should be good for at least a few more years of family use.

What's the consensus around here about transmission fluid? I know BMW claims the transmission is sealed and the fluid is for the lifetime of the vehicle, and I have zero issues with the transmission at this time, but really, shouldn't it usually be flushed/replaced around this mileage?

Those of you who have done a fluid change, any issues? And what was the cost?

[MH20jy]

Originally Posted by Amsterdave

My 2015 X5 35d has around 55,000 miles on it now and just came off its extended warranty with most major items (EGR, cat, control arms, air suspension bags) fixed or replaced while still under coverage, so should be good for at least a few more years of family use.

What's the consensus around here about transmission fluid? I know BMW claims the transmission is sealed and the fluid is for the lifetime of the vehicle, and I have zero issues with the transmission at this time, but really, shouldn't it usually be flushed/replaced around this mileage?

Those of you who have done a fluid change, any issues? And what was the cost?

ZF recommended 80k km so it's time for that. Fcpeuro sells transmission kits for around $300. Mine was at 65k now and I plan to do it soon. It's a cheap maintenance item and can save you a lot trouble later on.

[XxBBVTMxX]

I did my own right before 100k. The kit was just over $300, and I did the work myself. You can search for DYI on here.

After I changed mine, I got smoother shifting. Before I changed it, it had a slight pull in sports mode. I went with the original ZF fluid too.

[Chilled]

Originally Posted by Amsterdave

What's the consensus around here about transmission fluid? I know BMW claims the transmission is sealed and the fluid is for the lifetime of the vehicle, and I have zero issues with the transmission at this time, but really, shouldn't it usually be flushed/replaced around this mileage?

Those of you who have done a fluid change, any issues? And what was the cost?

Consensus = Do it.
Price = Cheap.

Btw, playing devils advocate. What is BMW's definition of "for life of vehicle", because I am willing to bet it's up to the Factory Warranty period or the National Statutory requirement around fit for purpose (ie 100,000km)

[M302_imola]

I'm at 109K miles and I'll be doing the tranny service soon. Hopefully ISTA isn't to hard to follow on the fillup procedure.

[XxBBVTMxX]

Just FYI for you DIYers,

When undoing the bolts that hold the trans oil pan in place, do not fully remove the front bolts. Remove all other bolts and very carefully pull down cover from the rear side, this way the remaining oil that is left in the pan will come backwards and you can catch it in your oil catcher.

After you have drained it through the check tube, there will still be a good amount of oil in the pan, as the oil check tube sits higher and not flush with the bottom of the trans oil pan.

This will avoid a huge oil mess 🤙🏽

Also, the whole service is pretty easy. Just take your time. The most impatient part is making sure you are at the temperature threshold, then check to see if you're good to go or need to add more fluid.

[chris323i]

Also a good idea to change your transfer case fluid while you are down there. The symptoms of old transfer case fluid can be pretty alarming (bucking on acceleration). No need for resetting parameters on that. I look forward to changing my transmission fluid soon with the kit from FCP. I'm at 99k with mostly TX highway miles. These ZF8s are such a great, versatile transmission. Hope to keep mine going for a while.

[MH20jy]

Originally Posted by XxBBVTMxX

Just FYI for you DIYers,

When undoing the bolts that hold the trans oil pan in place, do not fully remove the front bolts. Remove all other bolts and very carefully pull down cover from the rear side, this way the remaining oil that is left in the pan will come backwards and you can catch it in your oil catcher.

After you have drained it through the check tube, there will still be a good amount of oil in the pan, as the oil check tube sits higher and not flush with the bottom of the trans oil pan.

This will avoid a huge oil mess 🤙🏽

Also, the whole service is pretty easy. Just take your time. The most impatient part is making sure you are at the temperature threshold, then check to see if you're good to go or need to add more fluid.

I will have easy access to all screws even with the xdrive and don't need to drop any sub frame for tranny oil. Is that right?

[XxBBVTMxX]

Originally Posted by MH20jy

I will have easy access to all screws even with the xdrive and don't need to drop any sub frame for tranny oil. Is that right?

Negative ghost rider…

XDrive, you need something to support the gearbox as you need to drop the gearbox support.

There is 1… 1 freaking bolt blocked by this monstrosity 😒

So, support the gearbox, drop that stupid support, then you can remove that 1 bolt and have complete access to the rear of the trans oil pan. I would not recommend tackling this job if you don't have a lift to use!

(The bolt is being blocked by the area I marked with yellow) so… 5 needs to come out, then you can drop that support by removing the "I believe" 6 bolts.

[Chilled]

Originally Posted by M302_imola

I'm at 109K miles and I'll be doing the tranny service soon. Hopefully ISTA isn't to hard to follow on the fillup procedure.

My man, it's very simple. I would recommend to use something like BimmerLink tho. I had issues with ISTA connecting and doing full scan on all modules, as it would only do the scan and not fail with the engine running(this was prob my fault). But, by the time that full scan happened, 10ish minutes has gone by, and well I'm in the tropics so the temp was well into the mid 40°. So i decided to abort, try again when its cooled back down so I could do the fill at a more comfortable pace, and have ample time for the excess to drip out.

The only real advice I would give, is get a bitter filler jug. Mine was only a 1L, so I need to refill it during the top up process at 40°. This made it unnecessarily stressful.

Originally Posted by MH20jy

I will have easy access to all screws even with the xdrive and don't need to drop any sub frame for tranny oil. Is that right?

Depends on how you feel about spending on extra tooling, if you are ok with it, then no. You don't need to remove any supports or subframes, ect. Plus I'm personally against removing any supports unnecessarily.

As mentioned above, the access into the area is restricted, but once you are in there it does open up abit.

I personally got a cheap long hex(Allen) 14mm Socket and a Cheap 14mm Socket, that i cut down to size. It its in there perfect and i can use torque wrenches, no issues. Total cost half then the 14mm FCP option below.

Here is my experience doing it, and you can see a pic of the hex/socket and torque wrench. Post 161.
https://f15.bimmerpost.com/forums/sh...3#post28204123
Just FYI, you will need ether ISTA or a scan tool that can reset the adaptation (VTG) on the TC.
Another members diy.
https://f15.bimmerpost.com/forums/sh....php?t=1860683

Alternatively other members have used stuff like this.
https://www.fcpeuro.com/products/eur...m-box-cta-8762
or
https://tite-reach.com/
To get in there without dropping any supports.

[scotty339]

I had some warranty work done which required draining the transmission.They had to access the torque converter in the bell housing and they drained the trany.

They did not change the pan, which holds the magnets for the keeping the servos from plugging up, BUT, still new fluid... I'll take it. Shifts fine. If I had known that job would of required draining/dropping the tranny, I would of provided a new pan and paid the dealership labour. This was done @ 120k KM.

I may change the pan and fluid again @ 220K KM as I hope to keep till 300k KM.

To answer OP's questions... change the plan / fluid. Worth it. Not lifetime.

[Chilled]

Originally Posted by scotty339

I had some warranty work done which required draining the transmission.They had to access the torque converter in the bell housing and they drained the trany.

They did not change the pan, which holds the magnets for the keeping the servos from plugging up, BUT, still new fluid... I'll take it. Shifts fine. If I had known that job would of required draining/dropping the tranny, I would of provided a new pan and paid the dealership labour. This was done @ 120k KM.

I may change the pan and fluid again @ 220K KM as I hope to keep till 300k KM.

To answer OP's questions... change the plan / fluid. Worth it. Not lifetime.

If they didn't change the pan, then they did not change the oil filter. On Yours, the filter is built into the pan. Unless it has a metal Pan (factory only to the X5M/X6M), the plastic pans have the oil filter built in.


Other wise, hell yeah. Get all that oil out of TQ.

[Traveler99]

I had some problems on my 2015 x35i. Shifts overall were not very smooth and at very slow speeds, ie. backing into garage and stop and go traffic, there was a weird miss or stumble that you could feel. Kind of like a shopping cart with a bad wheel. According to my Foxwell scanner, no DTC's were registered and all live data was normal, ie. RPM, wheel speed... I thought about resetting adaptations, called the stealer and they were most unhelpful, listing no software updates or TSB's for that issue. So, I decided to start old school and change the transmission fluid to see if that would help. And of course then it progressed into a full driveline fluid change of the 'Lifetime' fluids. An Indie shop wanted $1600 for the job so that just pissed me off even more. Long story short, I followed the ZF instructions from their website, ordered ZF pan, ZF fluid from FPC Euro, changed the mechatronic sleeve, replaced the transfercase oil with genuine BMW stuff and used Redline 75w-85 GL-5 in the diffs. Been a couple hundred miles now and all the issues are resolved and the car shifts and runs great. I would say if you're having issues or thinking about doing it for preventative maintenance - don't hesitate to do it

[tlow98]

Originally Posted by Traveler99

I had some problems on my 2015 x35i. Shifts overall were not very smooth and at very slow speeds, ie. backing into garage and stop and go traffic, there was a weird miss or stumble that you could feel. Kind of like a shopping cart with a bad wheel. According to my Foxwell scanner, no DTC's were registered and all live data was normal, ie. RPM, wheel speed... I thought about resetting adaptations, called the stealer and they were most unhelpful, listing no software updates or TSB's for that issue. So, I decided to start old school and change the transmission fluid to see if that would help. And of course then it progressed into a full driveline fluid change of the 'Lifetime' fluids. An Indie shop wanted $1600 for the job so that just pissed me off even more. Long story short, I followed the ZF instructions from their website, ordered ZF pan, ZF fluid from FPC Euro, changed the mechatronic sleeve, replaced the transfercase oil with genuine BMW stuff and used Redline 75w-85 GL-5 in the diffs. Been a couple hundred miles now and all the issues are resolved and the car shifts and runs great. I would say if you're having issues or thinking about doing it for preventative maintenance - don't hesitate to do it

I’ll be using the same Red Line oil. Was happy to see its certified on their site!

Thanks for posting, I’m about to the full driveline change, as well. Sounds like you saved a bundle and the car works better. 💯

[tanda]

I'm struggling to find what tool or scanner to buy to read the ATF temp. Does anyone know which tool works for this?

[Clifton]

Originally Posted by tanda

I'm struggling to find what tool or scanner to buy to read the ATF temp. Does anyone know which tool works for this?

ISTA and Foxwell NT530 both work.

[tanda]

Originally Posted by Clifton

ISTA and Foxwell NT530 both work.

Much Appreciated!! think I've been trying to figure this out for weeks

[tlow98]

Originally Posted by tanda

Much Appreciated!! think I've been trying to figure this out for weeks

The Foxwell 530 will also reset your transfer case for you. Was easier than I thought to do that!

[Chilled]

You can also use Bimmerlink or the free Torque app. I personally used the bimmerlink app.

As someone who has the NT530, i would say don't waste your money on it and just use ISTA or see if the Torque app can see the trans temp correctly. Some apps confuse the trans temp for coolant.

Here is the difference in temps.

[Variante Alta]

I did the tranny and TC changes this past summer. No need to drop support bracket - recommend not doing it in fact even though access to the plug is a bit easier. I have ISTA and it worked just fine for both procedures. I got the FCP Euro kit with ZF fluid - the stuff reeks but I like OEM - in my books there's a reason there is ZF fluid. Worst part is being under the car while it's running to correctly fill the tranny - don't kid yourself with any shortcuts, you add a significant amount of fluid after the initial fill before warming and running the engine. Cheap insurance for a tranny I hope to 300+k from. Mine was running fine before the change so I can't comment on improvements - mine feels the same but there was crap in the filter and magnets. There are good DIYs for these services thanks to the great members of this community.

[BlackBeans]

I'm at 47k miles on my 50i at the moment, and hope to do the tranny+TC fluid services later this year as well. Thanks for the info guys

[compsyndrome]

Originally Posted by Variante Alta

I did the tranny and TC changes this past summer. No need to drop support bracket - recommend not doing it in fact even though access to the plug is a bit easier. I have ISTA and it worked just fine for both procedures. I got the FCP Euro kit with ZF fluid - the stuff reeks but I like OEM - in my books there's a reason there is ZF fluid. Worst part is being under the car while it's running to correctly fill the tranny - don't kid yourself with any shortcuts, you add a significant amount of fluid after the initial fill before warming and running the engine. Cheap insurance for a tranny I hope to 300+k from. Mine was running fine before the change so I can't comment on improvements - mine feels the same but there was crap in the filter and magnets. There are good DIYs for these services thanks to the great members of this community.

Did you not have trouble accessing all pan bolts? Maybe the M is different but the cross member of the support bracket seems to block access to one of the bolts on my 35D 2015.