[warev]

Almost 200k miles on an automatic e90 2006 330i. I don’t have a ton of knowledge on cars nor the right vocabulary to describe to exact issue, but the gears feel like they could shift smoother than have been lately. Auto shifter itself feels a little sticky when moving between Park-Drive. I don’t intend to fully service the transmission, but wanted to drain and replace the trans fluid. I’ve often heard that you should not touch old transmissions. Is this a myth? I could go without https://9apps.ooo/ doing this service, the driving isn’t horribly compromised, but it could be better.

[Bims328i]

If it's still running well at this point, changing the fluid and filter would be ideal and will likely not hurt anything. In most cases if you have torque shudder like I did, if it is fluid related, instant shudder fix will address the issue. If it is mechanically related then the shudder fix would likely not have affected the issue.

As yours isn't having much of any issue it should be a good preventative maintenance item to tackle.

I already did my filter and fluid change once but still need to change the fluid a few more times to really get it cleaned out. In my case the shudder fixx stuff really helped with my problem but it shows up from time to time driving in the city.

If you do decide to drop the pan and filter I would recommend using an inch pound wrench on the new bolts.

[StradaRedlands]

Change the fluid/filter. Too bad it wasn't done on time, but most aren't.

[mainbearing]

I have heard that myth, but I would rather have fresh fluid in the transmission and old. A drain and refill only changes out about half the capacity, therefore that may be a good compromise.

The filter is likely plugged to a good extent too, but I would not do both at the same time, in case you have concerns of introducing too much detergent from the fresh ATF.

[GoRomeo]

Originally Posted by warev

Almost 200k miles on an automatic e90 2006 330i. I don’t have a ton of knowledge on cars nor the right vocabulary to describe to exact issue, but the gears feel like they could shift smoother than have been lately. Auto shifter itself feels a little sticky when moving between Park-Drive. I don’t intend to fully service the transmission, but wanted to drain and replace the trans fluid. I’ve often heard that you should not touch old transmissions. Is this a myth? I could go without doing this service, the driving isn’t horribly compromised, but it could be better.

Had same issues like 5 yrs ago, I changed my solenoids, mechatronic sleeve gaskets and fluid at around 175k miles? Something like that. Tranny still working great after 5 yrs. Prob need to replace fluid soon.

[bmwbob89]

The only time it seems to be an issue is when you already have problems. Change the fluid and filter. I changed the fluid ran it a bit then changed the fluid and filter. That way you get a pretty good change of fluid. If it's a GM unit put a tube or 2 of shudder fix in . Cured my shudder issue at about 150k miles.

[Ali-E90]

I’d do it, and the diff fluid at the same time too.

[jbellk75rt]

I think what you are referring to is a flush rather than fluid and filter change. I've long heard not to do a flush (machine powered) on a high mileage tranny that hasn't had regular servicing. A simple fluid/filter change should be okay.

[michaelalex17]

The claim is that over time shavings from the clutches flow around in the fluid creating friction on the clutches, so when you drain that fluid and filter you lose all that friction which in turn causes slippage.

IF that is true it means your transmission is already on its way out anyway so changing the fluid would only be speeding up the inevitable. IF it’s not true then you’re breathing new life into your transmission.

So in either scenario you might as well just change it.

[Bims328i]

Yeap, if your transmission is still working relatively well like you describe then a fluid and filter change will likely just help. As other members have pointed out, you'll need multiple drain and fills to get all the old fluid out.

I really need to do a couple drain and fills on my ride. Just curious now with simple drain and fill. Do we just drain then fill until it spills out? I dropped my pan almost a year ago and had to run it through gears to get the right amount of fluid in the system.

[jadams161]

Myth. If you want to do it correctly then buy mechtronics seal kit, fluid and filter. Depending on how the fluid looks, I would also consider doing a drain and fill again after driving a few hundred miles. Also you didnt say if it is a ZF or GM trans, but the GM (some years?) need that shift linkage replaced too.

[StradaRedlands]

Originally Posted by Bims328i

Just curious now with simple drain and fill. Do we just drain then fill until it spills out? I dropped my pan almost a year ago and had to run it through gears to get the right amount of fluid in the system.

I imagine you still need to go through the entire process of getting it to temp and going through all the gears, even with a drain/fill.

[dwall]

Changing the fluid could improve the shifting, but it's not a sure thing. If you're comfortable with it, give it a shot it's pretty straightforward.

[crashoverride]

True story I took my car to the dealership and they refused to just drain and refill and replace filter (filter is part of the cover) at 125k miles. They said after something like 90k they won't replace the fluid. I think they are ignorant.... but alas with 225k miles I haven't done anything and I'm sure my fluid is well past it's prime.

[Cloverdale]

'The claim is that over time shavings from the clutches flow around in the fluid creating friction on the clutches, so when you drain that fluid and filter you lose all that friction which in turn causes slippage.'

This claim is well supported and represents a significant risk in respect to a higher mileage non serviced auto trans. How certain are you that yours hasn't been serviced?

[Onizukachan]

The shifter mechanism has nothing to do with the trans itself.


And having lost a trans due to doing a fluid change I would be hesitant to recommend you change it, except to change it to a manual, lol.

[jadams161]

Originally Posted by Onizukachan

The shifter mechanism has nothing to do with the trans itself.


And having lost a trans due to doing a fluid change I would be hesitant to recommend you change it, except to change it to a manual, lol.

You didn't "lose a transmission" from a fluid change. You lost it because of a LACK of maintenance and fluid changes. So many people ignore the fluids in the cooling system, brake system, transmission, transfer case, front and rear differentials, and blinkers. Its complete nonsense that BMW goes against what GM France and ZF clearly state as the recommended service intervals. BMW for all the shit they rip people off for at the dealerships could be making so much revenue on doing driveline services. The want you to change the brake fluid every 12 months (and thats just under compression in sealed lines) while telling customers that the fluid in a transmission, that is under extreme stress, heat and friction, that it is "lifetime".

[lordnikon]

Originally Posted by jadams161

You didn't "lose a transmission" from a fluid change. You lost it because of a LACK of maintenance and fluid changes. So many people ignore the fluids in the cooling system, brake system, transmission, transfer case, front and rear differentials, and blinkers. Its complete nonsense that BMW goes against what GM France and ZF clearly...

[lowrydr310]

Originally Posted by Cloverdale

'The claim is that over time shavings from the clutches flow around in the fluid creating friction on the clutches, so when you drain that fluid and filter you lose all that friction which in turn causes slippage.'

This claim is well supported and represents a significant risk in respect to a higher mileage non serviced auto trans. How certain are you that yours hasn't been serviced?

I think the bigger risk is a FLUSH versus a simple drain and fill. I'd avoid a flush on any transmission. Drain and fill shouldn't affect anything.

I bought a 220K mile 325i with the ZF 6HP transmission and it wasn't shifting smoothly. Occasionally the transmission would make a screeching sound at high RPM shifts. I took it to a local independent BMW shop and they advised against a drain and fill, so I did it myself. It SIGNIFICANTLY improved the shifting and overall feel of the transmission, and eliminated that screeching sound.

[lowrydr310]

Originally Posted by Onizukachan

The shifter mechanism has nothing to do with the trans itself.


And having lost a trans due to doing a fluid change I would be hesitant to recommend you change it, except to change it to a manual, lol.

Which transmission did you lose?

Just curious because for the ZF 6HP, the car has to be running in order to fill it to the correct level. I can easily see a scenario where someone services this transmission and fills it while the car isn't running, in which case it wouldn't have the proper amount of fluid, which could easily lead to damage.

[BRG_N54]

Originally Posted by lowrydr310

I can easily see a scenario where someone services this transmission and fills it while the car isn't running, in which case it wouldn't have the proper amount of fluid, which could easily lead to damage.

Or, perhaps more catastrophic, the car is running, but the fluid level exceeds 50C and expands, leaving too little fluid for normal operation. Either way, yes you could ruin a perfectly good transmission by missteps in this fill/drain process.

[Onizukachan]

4l30e with real ATF3.

And yes I know all about the running whilst filling and cycling thru the gears to make sure the tc and passages are all filled amd being up to temp etc. It was done right.

Still killed it.

Op has no problem with the trans, but with feeling the shifter is stiffer when moving form park to drive. That’s no tramdps issue, that’s a shifter mech issue