Gearbox oil change - how often? - Page 2

sew · #1 02-24-2016, 01:28 PM

Thanks @Rosssavage, looking at Bentley it seems the pan is seperate and I believe I do have the relevant tools to do the job (incluing checking the fluid temperature). But I'd still need to get the correct fluid and filter from BMW themselves, so all I'd be saving is the labour charge.
Still not sure when I need to do it next...!

Rosssavage · #2 02-24-2016, 01:56 PM

Just been watching the bavauto video - yup, looks like the filter is a separate part and can be replaced independently.

bcredliner · #3 02-24-2016, 02:32 PM

There are strong feelings on to change or not to change. The vast majority of the time the not to change contingent bases their opinion on the BMW statement that the fluid is for the lifetime of the transmission. As noted, there is often mention that it will cause problems.

The change folks base their opinion on fluid degradation.

Changing the fluid and filter is an easy DIY and having the capability to take the temperature of the fluid is not critical. As long as the fluid is full, which means there is a small steady stream running out of the fill hole after the transmission has been filled and also after the vehicle has be cycled through the gears and the vehicle is driven but not hard for a few miles and then the fluid is topped off it will be fine.

The filter is completely separate from the pan. I don't think there is any reason to use other than the proper ZF fluid.

If you decide to change the fluid, how often is up to you. My interval is every 50,000 miles.

SlickGT1 · #4 02-24-2016, 03:01 PM

Quote:

Originally Posted by bcredliner

There are strong feelings on to change or not to change. The vast majority of the time the not to change contingent bases their opinion on the BMW statement that the fluid is for the lifetime of the transmission. As noted, there is often mention that it will cause problems.

The change folks base their opinion on fluid degradation.

Changing the fluid and filter is an easy DIY and having the capability to take the temperature of the fluid is not critical. As long as the fluid is full, which means there is a small steady stream running out of the fill hole after the transmission has been filled and also after the vehicle has be cycled through the gears and the vehicle is driven but not hard for a few miles and then the fluid is topped off it will be fine.

The filter is completely separate from the pan. I dot think there is any reason to use other than the proper ZF fluid.

If you decide to change the fluid, how often is up to you. My interval is every 50,000 miles.

+1.

I try to keep it at 30k on previous cars.

itscoo2pyopants · #5 02-24-2016, 04:29 PM

Quote:

Originally Posted by SlickGT1

+1.

I try to keep it at 30k on previous cars.

me too, every 30k miles I do the driveline fluids. cheap insurance IMO

sew · #6 02-24-2016, 03:26 PM

Thanks all. I think I'll aim for around 40k intervals where possible.

sew · #7 02-25-2016, 03:21 AM

@oldskewel I think I understand now what you're saying. I'd hope anyone contemplating a task like changing the auto box oil would do their homework first. I have non-BMW oils in the engine and final drives, but (primarily becuase it's not possible to drain and refill completely and I wouldn't feel happy mixing them) I'd only use "BMW" oil in the gearbox, and I'd make quite sure it was the right stuff!

StephenVA · #8 02-25-2016, 11:02 AM

Oldskewel
Thanks for all the insight you posted. The approach and methodology is exactly the way to service any part especially hi-end auto transmissions.

For those who have ZF transmissions there is a host of info on the web besides here if you would like to know more. One suggestion is the manufacturer's own site ZF Friedrichshafen - ZF Friedrichshafen AG There are down load service procedure manuals and lube recommendations (one of which is attached to this posting). Great insight.

Thanks again for posting your efforts and results. I am sure we will continue the battle of "to change or not to change". IMHO fluid life at 10 years is the point of replacement and filter change time, period. No lube manufacturer recommends using fluids in a sealed bottle at that age much less keeping them in service.

oldskewel · #9 02-25-2016, 05:19 PM

Quote:

Originally Posted by StephenVA

...Thanks again for posting your efforts and results. I am sure we will continue the battle of "to change or not to change". IMHO fluid life at 10 years is the point of replacement and filter change time, period. No lube manufacturer recommends using fluids in a sealed bottle at that age much less keeping them in service.

Yes, after thinking about it a little more I realize there is actually a very important similarity between the ZF and GM ATs - now they are both, in many cases, in a predicament due to BMW's "lifetime" ATF policy. And what do you do now - keep believing in "lifetime" or try to carefully work your way out of the problem? That is the same for ZF and GM.

So that very important aspect is similar between the two.

StephenVA · #10 02-25-2016, 06:56 PM

Change the fluid as preventive maintenance.
One or two posters of the X5 forum do long daily drives and now show 200K+ mileage with the original trans and fluid. The rest of us do not have that type of driving patterns. I think everyone recognizes that trans wear occurs on shifts not hi gear runs down the hwy. A fluid and filter change is a good thing.