[Afanz]

So back in October I bought an E90 328 Xi with the GM transmission in it. The car has 102,400 miles on it and I'm wondering if I should change the transmission fluid in it? It will be the cars first transmission fluid change. I've heard stories of people changing it at this mileage and it destroying the transmission. Is it worth risking it? I don't have any transmission problems, shifts very smooth. Also if I do it what advice or tips does anyone have? Fluid brands? Thanks!

[ryan stewart]

Where have you heard of a fluid change ruining it?

According to gm you should have already done it twice.

[Afanz]

Originally Posted by ryan stewart

Where have you heard of a fluid change ruining it?

According to gm you should have already done it twice.

Originally Posted by ryan stewart

Where have you heard of a fluid change ruining it?

According to gm you should have already done it twice.

Some people on the forum have said that it will loosen sediment in the transmission and will make it worse. I would have changed it by now but I just got the car and I am doubtful that it has ever been changed.

[ricx]

Change the fluid now or change the trans later. Don't believe the life time BMW lie.

[mecheng77]

Yes change it, that is the exact mileage for the first change

[ryan stewart]

Originally Posted by Afanz

Some people on the forum have said that it will loosen sediment in the transmission and will make it worse. I would have changed it by now but I just got the car and I am doubtful that it has ever been changed.

It doesn't really work that way. There is a filter in the sump.

Change the mechatronics sleeve and the manual valve while in there, along with filter obviously

[nsjames]

Originally Posted by Afanz

Some people on the forum have said that it will loosen sediment in the transmission and will make it worse. I would have changed it by now but I just got the car and I am doubtful that it has ever been changed.

literally the recommended mileage for the GM regular service schedule.

change it and the filter now.
change the fluid again in 50K.
change fluid and filter again at 200.

that's the severe duty schedule.

I changed mine at 102K miles after I bought the car without a second thought.
now at 156K miles with a properly functioning transmission that is due for fluid again.

at no point will changing the fluid in a properly working transmission harm it.
you're only going to prolong it's life.

and if it's an XI model you should strongly consider servicing the transferbox as well and doing the reset so it adjusts for wear.

[colorado.e9x]

My 330xi is at 140k almost and I'm fairly certain the 'lifetime' fluids have never been changed. Better to do it late than never?

[C4maro]

The fear is that when you change fluid that hasn't been changed in a really long time you run the risk of emptying fluid that has particles built up over time from the transmission which allows for more friction between plates or something, then adding new fluid it could slip not having that debris in the fluid. No idea if this is true but it kind of makes sense.

There probably is the odd horror story but I imagine it's going to be a really good thing for the trans 97.23% of the time.

[tlow98]

this again?

do some searches on here and look at the number of people that have positive experiences changing their fluid and the number of people that have negative experiences. cliffnotes; it's a lot of people to zero people, respectively.

[Efthreeoh]

If the car has the original set of manuals, you'll find in the maintenance manual that the automatic transmission oil service interval is 100,000 miles. BMW spec is to change the auto trans fluid at 100,000 mile intervals.

[ryan stewart]

Originally Posted by tlow98

this again?

do some searches on here and look at the number of people that have positive experiences changing their fluid and the number of people that have negative experiences. cliffnotes; it's a lot of people to zero people, respectively.

And Id be suspect of someone changing it at 100k claiming it broke their transmission. They either did something wrong or its completely unrelated.

OP when you do make sure and take your time to clean really well. There was a LOT of particulate and metal coating the inside of my pan. That way you are making life as easy as possible for the next filter you put in.

[TheMidnightNarwhal]

Originally Posted by ryan stewart

And Id be suspect of someone changing it at 100k claiming it broke their transmission. They either did something wrong or its completely unrelated.

OP when you do make sure and take your time to clean really well. There was a LOT of particulate and metal coating the inside of my pan. That way you are making life as easy as possible for the next filter you put in.

Isn't the filter part of the pan ergo a new pan goes in anyways?

[ryan stewart]

Not on the GM transmission, its the old school filter in a metal pan. The ZF one though is the plastic pan/filter combo.

There is a magnet that looked like one of those iron filings toys but the rest of the pan was coated in a greyish fluid where the old transmission fluid had coagulated and had a lot of microscopic metal suspended in it (looked like metallic paint basically).

After shot of how you want it to look:


Before was coating in something that looked not unlike this:
https://cdn.shopify.com/s/files/1/23...g?v=1555361322

[401FlaGATOR]

I did mine at 90k first time and it survived..did it again at 156K. I'm at 194K still going strong.

[nsjames]

Originally Posted by colorado.e9x

My 330xi is at 140k almost and I'm fairly certain the 'lifetime' fluids have never been changed. Better to do it late than never?

yes.

Originally Posted by C4maro

The fear is that when you change fluid that hasn't been changed in a really long time you run the risk of emptying fluid that has particles built up over time from the transmission which allows for more friction between plates or something, then adding new fluid it could slip not having that debris in the fluid. No idea if this is true but it kind of makes sense.

There probably is the odd horror story but I imagine it's going to be a really good thing for the trans 97.23% of the time.

an old wives tale.
There's a filter on the pump.
ask most of those people that say that and they'll tell you that they've never experienced it, or the transmission was already slipping and they tried changing the fluid to fix a hard part problem.

I've experienced changing transmission fluid on everything from 60K mile units to 280K mile ones, and in every case it worked better after fresh fluid.
literally dozens of transmissions.
mostly high mileage beater shitboxes I bought for scrap value, fixed and drove for the next year.

[CTinline-six]

Originally Posted by nsjames

yes.



an old wives tale.
There's a filter on the pump.
ask most of those people that say that and they'll tell you that they've never experienced it, or the transmission was already slipping and they tried changing the fluid to fix a hard part problem.

I've experienced changing transmission fluid on everything from 60K mile units to 280K mile ones, and in every case it worked better after fresh fluid.
literally dozens of transmissions.
mostly high mileage beater shitboxes I bought for scrap value, fixed and drove for the next year.

+1

Trans fluid drain and fills with the correct fluid will only prolong the life of the transmission. Those who experienced issues either didn't use the correct amount of fluid, used the wrong fluid type, or used a flush machine. Power flush machines are a big no-no because they can cause any contaminants that might be in the transmission to get pushed into the shift solenoids.

[rt7085]

I changed it at 95k and I am at 118k and going strong. Change it. And change the oil in the 4WD clutch as well. Why not. Put new oil plugs. Make sure you torque the pan bolts properly and in the right order.

[shh125]

You can change the transmission fluid, but if the transmission starts slipping or performing poorly after the fluid change, you can drain the new fluid and refill it with the old/original fluid. It's important to keep the old fluid clean and prevent further contamination during removal.

​Don't skip changing your transmission fluid just because someone else had a bad experience.


Here's a step-by-step how I would do it:

1- Clean the transmission bottom and the area under your car where the transmission is located to keep dirt out of the fluid.
2- Use a clean drain pan/ container to catch the old fluid when draining it.
3- Pour and store the old fluid into a clean container using a strainer or funnel to catch any debris.
4- Label the container as "Old Transmission Fluid" so you know what it is.
5- After replacing the filter and refilling with new fluid, If your transmission still isn't working right after the fluid change, switching back to the old fluid might help.


My transmission was occasionally jerking when I was at red lights. I changed the transmission filter and fluid, and the jerking is almost gone. I made the change at 50k miles or 80k, kilometers. Mine is a 2011 328i E93 with the GM GA6L45R Automatic Transmission. Since we cannot drain the fluid in the torque converter, I drained and refilled it about two times, but you don't have to do it.

I had the same hesitation that changing the fluid might worsen the problem, but it worked perfectly for me, and I will do it again soon.

Remember, don't dismiss changing the transmission fluid solely based on someone else's experience.

You won't know for sure until you try it. Avoiding a fluid change based on another's experience isn't wise; various factors could have contributed to their issue, such as the transmission type or other factors

One thing is certain: neglecting fluid changes can harm your transmission over time. It's worth testing and changing the fluid, potentially saving your transmission in the long term.

If your transmission still struggles after the fluid change, switching back to the old fluid may be worth considering.

[Captain Buumer]

Worn clutch plates start slipping with fresh fluid since the abrasive material is gone.
Old burnt fluid filled with contamination is providing the abrasion.

But reaching this point means soon gears won't engage and need to replace transmission anyways due to accelerated wear.

I suppose it's a good indicator if you need to prepare for new transmission or not.

[Bmw1939]

The old tranny fluid sediment disc argument applies to the old transmissions from back in the day I believe.