[skohlhepp]

Hi all, I am sure this topic has been discussed a bunch here and elsewhere. I'm driving a 2012 535i with close to 110k miles on it now. It has been FBO Pure Stage 2 with the corresponding MHD OTS engine map and an XHP Stage 3 Transmission tune since about 80k miles.

What if anything should or could I do in terms of preventative maintenance for the transmission? FCP Euro sells the kit with the new plastic pan & filter & ZF LifeGuard fluid but I have only read of folks doing that maintenance at a much lower mileage than mine. Is it best to just ride it out until something breaks or could I (Or pay a shop to) still safely change out the fluid? The adaptation values and quickcharge times are still within a good range according to the XHP diagnostics.

Thanks!

[95blkmax]

Do it. You won't regret it. I did it at about 115k on my 2011. I used FCP's kit with LiquiMoly TopTec1800 fluid and ZF pan. Zero issues in the 3 yrs since doing that.

Trans felt much more responsive. I felt that improvement on stock trans tune (I did this long before I went xHP). So I think you being on xHP already would see an even larger improvement

[SWFLf10]

I agree with the above. I did mine at 105,000 miles using the FCP kit with the ZF fluid and haven’t had any issues since, and I’m now at 166,000 miles.

Easy process if you follow the online guides and use ISTA for the procedure.

[ctcarbonari]

+1 to performing the Service per ZF recommendations regardless of mileage.
I'm personally not a believer in "It's too late to change the fluid now" thought process.

I'd recommend replacing your mechtronic sleeve while you're at it (as PM).

Also, consider doing a "dump & fill" w/ new fluid first - then a couple hundred miles later doing the full service pan/filter replacement procedure. This will get you about 85% New Oil in your system.

-Attached is ZF Service Info for 8HP Transmission (for those that haven't seen it before)

[bk_mike]

Originally Posted by ctcarbonari

I'm personally not a believer in "It's too late to change the fluid now" thought process.

I second this. The days of sludge holding together your transmission and keeping it going are long gone...

[skohlhepp]

Thanks for all the feedback. I went ahead and replaced the fluid and put in the new pan / filter combo and everything seems to be very smooth so far! I did however forget to do the mechatronic sleeve while I was in there. What is the concern level for something like that failing and is it something I should prioritize and take the pan back off soon?

[95blkmax]

Originally Posted by skohlhepp

Thanks for all the feedback. I went ahead and replaced the fluid and put in the new pan / filter combo and everything seems to be very smooth so far! I did however forget to do the mechatronic sleeve while I was in there. What is the concern level for something like that failing and is it something I should prioritize and take the pan back off soon?

not really. It would have been nice to have done it while in there, but not a big deal. That seal is not a common leak on the 8HP. It was a notorious leak point on the 6HP. I would not worry about it bro. I did my fluid change like I said 3 years ago... and I too did not change the sleeve, lol. Not leaking still!

[OnlyGerman]

I did it at higher mileage using FCP kit

[ctcarbonari]

Originally Posted by 95blkmax

not really. It would have been nice to have done it while in there, but not a big deal.

Agree. It's a relatively inexpensive PM item to catch "while you're in there".
I wouldn't go out of my way to replace it now. Catch it on the next fluid/filter service.

The important thing is that you changed out part of your "lifetime fluid" (and filter).