[Scotchydog]

Hi - I’m new to the forum I’ve owned a E90 320d manual for 2 years and now got a 2013 F30 335d Xdrive - it has done 85500 miles which includes 2500 that I’ve put on myself - keep seeing a lot about getting the fluid flushed out and and genuine service/oil and filter kit being done at either 62k or 8 years - the car as been looked after and as high milage for its age (taking that is a good point) but was thinking getting it done for £400 at a transmission specialist - does anyone think it’s the right time, as it been long overdue or could you take it further

[Gen13 F36]

I totally set on 65,000 miles on MY2016 428i GC. Currently at 21k miles.

[adhrp]

This is something I was ambivalent about until recently. Then, someone posted on here that they had over 150k on their original fluid and that the transmission was running fine. More recently, there was another post where someone changed it around 60 or 80k and the fluid looked fine and the transmission pan had very little metal residue on it. With that info in hand, I have decided to not change the fluid at all. If you search recent threads on this topic, you will come across the posts I mentioned.

[Scotchydog]

Thanks for the reply’s and yeah I’ll have a look cheers

[Wgosma]

Originally Posted by adhrp

. More recently, there was another post where someone changed it around 60 or 80k and the fluid looked fine and the transmission pan had very little metal residue on it..

See comments/recommendations near bottom of P-1 of the attached - visual inspection of a lubricant (trans fluid, motor oil, etc.) is near worthless, to know the status a fluids lubrication properties one needs a lab analysis.

Good Luck/Bill

[adhrp]

Originally Posted by Wgosma

visual inspection of a lubricant (trans fluid, motor oil, etc.) is near worthless

Good Luck/Bill

True, but I think it is worthless the other way around - i.e. darkened fluid doesn't necessarily mean it is bad. OTOH, if the fluid looks like it has hardly changed color from new...seems to me that that tells you something about the fluid. But yes, I agree that a full lab analysis would be much more worthwhile. I just haven't seen a lab analysis anywhere of the ATF fluid for our cars.

[XxThe_RemedyXx]

Did mine at 57K with the FCP Euro kit. Trans loves the new fluid and shifts are smoooth. My lab analysis of transmission fluid...

[Wgosma]

Money well spent on this major driveline component 👍

[jparnes1]

Originally Posted by adhrp

This is something I was ambivalent about until recently. Then, someone posted on here that they had over 150k on their original fluid and that the transmission was running fine. More recently, there was another post where someone changed it around 60 or 80k and the fluid looked fine and the transmission pan had very little metal residue on it. With that info in hand, I have decided to not change the fluid at all. If you search recent threads on this topic, you will come across the posts I mentioned.

Think about this...why do you change your engine oil? It gets dirty? Metal particles create friction? The protective properties of the oil break down? Why is the oil in your tranny (or diff or transfer case) any different? Your sample size of 1 at 150k miles doesn't make a strong case. ZF itself recommends new fluid at 60k. I get it.. .you don't want to pay for this service. I think that's short sighted if you plan on keeping the car.

[metallicpea]

Given my personal experience with previous high mileage BMWs and a few ZF transmissions in other makes, the old oil does start to not look good at about 80k or 8 years - depending on use, and I have noticed physical effects on the transmission between 85k and 110k miles - 7 to 9 years, so I am in the camp that I would not go past maybe 65 to 75k depending on conditions.

If you don't plan to keep the car that long, you can just say it's the next guy's problem, but even if I were planning to sell before 75k I would still spend to swap out the fluid at least, save the planet and all.

Really environment and driving habits do effect it as well. If it is mostly long distance highway use in a temperate climate, you can certainly go longer. I have quite mixed driving and hot and cold climate extremes, so mine is probably rougher than average on the fluids.

I am not super insane on fluid maintenance, but engine oil, trans fluid and coolant are the three I don't cut corners on. Not the frequency or quality of parts and fluid.

[sspade]

Im currently at 64k and plan to replace pan and fluid around 70k.

Still debating on paying the dealer $700 or spending $400 myself and having the stress of the DIY to worry about.

Anyone else get a dealer quote ?

[Wgosma]

$700 from dealer seems good price. I had two independent shops here in SoCal quote me $800 and $1100.
Good luck/Bill

[sspade]

Originally Posted by Wgosma

$700 from dealer seems good price. I had two independent shops here in SoCal quote me $800 and $1100.
Good luck/Bill

Thats what I thought!

Niello BMW, Elk Grove CA

Have it in writing...

[jparnes1]

Originally Posted by sspade

Im currently at 64k and plan to replace pan and fluid around 70k.

Still debating on paying the dealer $700 or spending $400 myself and having the stress of the DIY to worry about.

Anyone else get a dealer quote ?

It's not a bad diy. If you have an xdrive you'll likely have to drop the front drive shaft. Other then that, no biggie. And get a laser thermometer as the fill is temperature dependent.

[adhrp]

Originally Posted by jparnes1

Think about this...why do you change your engine oil? It gets dirty? Metal particles create friction? The protective properties of the oil break down? Why is the oil in your tranny (or diff or transfer case) any different? Your sample size of 1 at 150k miles doesn't make a strong case. ZF itself recommends new fluid at 60k. I get it.. .you don't want to pay for this service. I think that's short sighted if you plan on keeping the car.

I agree that N=1 is not a strong sample size. But that is the only datapoint I have. Of course, fluids do eventually breakdown to a point where they no longer do their job. But what is that point?

While I am very proactive about all my car's maintenance care, I do not see myself keeping it beyond 2022/130k miles and therefore do not plan to drop a grand on this service. I really do not believe the transmission will fail before then or even soon after based on the way it is behaving right now (84k miles). So for my personal situation, I am at peace with this decision. May turn out to be a mistake, but then at least I can contribute a datapoint to this forum saying that my transmission failed because I did not change the fluid for 130k miles.

[adhrp]

Originally Posted by XxThe_RemedyXx

Did mine at 57K with the FCP Euro kit. Trans loves the new fluid and shifts are smoooth. My lab analysis of transmission fluid...

Seems like the oil is holding up well!

[Polo08816]

Originally Posted by Wgosma

See comments/recommendations near bottom of P-1 of the attached - visual inspection of a lubricant (trans fluid, motor oil, etc.) is near worthless, to know the status a fluids lubrication properties one needs a lab analysis.

Good Luck/Bill

It is interesting that part of the procedure has you overfill the transmission by 0.5L.

[Gen13 F36]

Why can't they just design a more conventional ZF transmission where you can just drain them through a drain hole....then just and fluid. Why is the oil pan need replacing why why why it just hold the oil

[XxThe_RemedyXx]

It seems so. Hope it stays that way

Originally Posted by adhrp

Seems like the oil is holding up well!

[Wgosma]

Originally Posted by Gen13 F36

Why can't they just design a more conventional ZF transmission where you can just drain them through a drain hole....then just and fluid. Why is the oil pan need replacing why why why it just hold the oil

...German Engineering 😉. The fluid's filter is integral to the plastic pan assembly.

[sspade]

Anyone close to 95624...

who wants to do this together, PM me. I have a garage and tools.

BimmerLink also has two different trans temp readings available to us.

I believe one other member is interested as well.

[upsidedownfunnel]

ZF recommends a 62k mile (100k km) change interval for the ATF. I'd go with the company that created the transmission as the best recommendation. They recommend a maximum of 8 years in between ATF changes. The process is easy enough for a home mechanic to do and cheap enough for a good indy shop to do.

A transmission fluid flush is cheap insurance. If you're the type that doesn't really care about how their car runs, sure let it go to 150k miles. It'll "work" but it won't be optimal. Spend a couple hundred bucks and keep your transmission running well. The ZF 8HP has very tight tolerances and letting the transmission fluid go too long could negatively affect its performance. What makes the 8HP such a good transmission is that it feels so fast and precise when it shifts. You will lose that if you let old fluid stay in there for so long.