DB9 Auto Box Oil Change

[David Ramsbotham]

I know the auto box is supposed to be filled for life but wondered what views there might be on actually replacing all the oil in the transmission as the vehicles age/accumulate miles?

Also is this an easy task, anyone actually carried this out for themselves?

Thanks David.

[MarkwG]

I don't have an Aston (yet...) but I have a similar ZF box in my daily driver. Any competent auto gearbox specialist will be able to handle it, although sealed for life ZF recommend & sell service packs for them. The job can be handled at home or I imagine by an Aston dealer/specialist, but I feel it's better to use someone who understands the problems of draining the fluid properly & flushing it correctly. I've had a few done over the years, makes a difference as the fluid degrades over time as well as use. My specialist recommends max 5 years/50k. HTH.

[Hutch525]

I did mine and the difference is night and day.
Mines a 2004 with 92,000 on it.
You get used to the car as you drive it,
But a few hundred pound for filters and oil is more than worth the effort.
Top tip though only use ZF filters and the lifeguard 6 oil. There is a difference in the zf 5 gear box oil and the zf6 gearbox oil we have. Its more expensive, but don't be tempted to skimp to save a few pounds.
We have the same(but different) gear boxes fitted to jags and bmw's the 6hp26. So there is lots of information on the forums when you start looking into it.
Also alot of info if you get harsh downshift and if you need to replace seals or rebuild the mechatronic unit.
I rebuilt the mechatronic with a sonnax zip kit and all new solenoids.
The difference in the drive is amazing

[ian448]

Have a look at Aston1936 full write up / video of the process

[SHIFTY]

Have a look at

https://aston1936.com

[LTP]

David Ramsbotham said:

I know the auto box is supposed to be filled for life but wondered what views there might be on actually replacing all the oil in the transmission as the vehicles age/accumulate miles?

I took my old V70 to an independent transmission specialist and he told me that the "sealed for death" approach was imposed by the OEMs on the transmission suppliers in a drive to reduce servicing for customers, the actual transmission manufacturers would have preferred an oil change at about 60k miles. He also said that the current generation of cars is increasingly specifying a transmission oil change - I can't confirm this for all cars and my 2019 V60 still says that "the transmission fluid does not need changing during the life of the gearbox except in adverse driving conditions" (my emphasis).

I wouldn't have thought that replacing old oil with fresh could do anything other than good, unless the transmission has some sort of learning and compensation system that would need to be reset.

[David Ramsbotham]

Great responses, thank you all very much

[Jon39]

I experienced the need for an autobox to be filled with new oil.

The gears began behaving in an odd way. Even trying to use the alternative manual gear selection, did not always work as it should.
An oil seal leak was the culprit. When the oil level in the gearbox dropped, gear changes and hill starting did not work as expected.

Full of new oil and all was well.

When the manufacturers proudly boast, filled for life, what length of life do they really expect?

[LTP]

Jon39 said:

When the manufacturers proudly boast, filled for life, what length of life do they really expect?

Typically 8 years/80,000 miles or 10 years/100,000 miles

[MarkwG]

Jon39 said:

When the manufacturers proudly boast, filled for life, what length of life do they really expect?

My suspicion is the car manufacturers boast is different from the gearbox manufacturers expectations: the car company mean the expected lifespan that the first owner will use the car for, ie probably 3 years/45000 miles on average. They're not interested in owner 2, they'll most likely have third party warranty anyway, if they have any warranty at all; the gearbox company mean as long as you want, provided you follow their service regime... I suspect what they mean by "life time" & "sealed for life" is that there's no expectation that you'll need to top up the fluid or apply any other maintenance before the fluid reaches its service life. I can't find it in the ZF literature online, but I've seen before that ZF expect that to be 120000 km/8 years - kms, not miles, that's roughly 70000 miles, & that's normal use, not extended hot running or abuse. They're also clear that an early change isn't detrimental.

The car companies want to minimise the service cost of the car, to make it commercially acceptable to the first owner. To infer it'll need a relatively expensive gearbox service before the end of their tenure doesn't suit their case, & in reality, is unlikely anyway, exceptional business use aside. What it could do, is make the second owner less likely to buy, knowing there's a relatively large service due within their tenure, which potentially depresses the cars secondhand value, & that does affect owner 1. Autoboxes can fail suddenly, but usually it's a gradual decline in performance leading to a failure quite a long way down the track - so it becomes a problem they can offset to someone else, because it may not happen anyway. That may sound a little cynical, but it's the commercial reality, I suspect.

It's interesting that in US, where autoboxes are far more common, & have a longer history, an auto trans service is part of normal life, & often drive in/drive out. Since the technology is pretty much the same (discounting the more modern DSG etc), it makes you wonder why that's not the same here.

[oilit]

MarkwG said:

My suspicion is the car manufacturers boast is different from the gearbox manufacturers expectations: the car company mean the expected lifespan that the first owner will use the car for, ie probably 3 years/45000 miles on average. They're not interested in owner 2, they'll most likely have third party warranty anyway, if they have any warranty at all; the gearbox company mean as long as you want, provided you follow their service regime... I suspect what they mean by "life time" & "sealed for life" is that there's no expectation that you'll need to top up the fluid or apply any other maintenance before the fluid reaches its service life. I can't find it in the ZF literature online, but I've seen before that ZF expect that to be 120000 km/8 years - kms, not miles, that's roughly 70000 miles, & that's normal use, not extended hot running or abuse. They're also clear that an early change isn't detrimental.

The car companies want to minimise the service cost of the car, to make it commercially acceptable to the first owner. To infer it'll need a relatively expensive gearbox service before the end of their tenure doesn't suit their case, & in reality, is unlikely anyway, exceptional business use aside. What it could do, is make the second owner less likely to buy, knowing there's a relatively large service due within their tenure, which potentially depresses the cars secondhand value, & that does affect owner 1. Autoboxes can fail suddenly, but usually it's a gradual decline in performance leading to a failure quite a long way down the track - so it becomes a problem they can offset to someone else, because it may not happen anyway. That may sound a little cynical, but it's the commercial reality, I suspect.

It's interesting that in US, where autoboxes are far more common, & have a longer history, an auto trans service is part of normal life, & often drive in/drive out. Since the technology is pretty much the same (discounting the more modern DSG etc), it makes you wonder why that's not the same here.

I agree - its about lease costs and service costs for most cars - accepting that not that many AM will be leased as company cars where getting a car into a price budget per month (compared to say a BMW or Mercedes/Ford etc)

[Mossquire]

I bought my DB9 four years ago and decided to change all the fluids just to give me the piece of mind. I did the research on the sealed for life gearbox and ad an article from an ex ZF engineer who sid that the SFL policy was, in a large part due to checking boxes which had been returned to them for refurbishment. They concluded that the damage was primarily caused by grit ingress when the oil had been checked/topped up/changed. They decided that it would be better not to have the check replace as the box would, without any obvious leak, last long enough to be years out of warranty. His advice was clean, clean, clean before you open the fill plug.

[TarquinMX5]

The above makes sense. Jaguar used to say sealed for life but later changed that. If it was mihe, I'd change it; irrespective of warranty time scales, many manufacturers seem to work to a 7-year vehicle life from what I've read over the years.

[Dewi 2]

TarquinMX5 said:

..... many manufacturers seem to work to a 7-year vehicle life from what I've read over the years.

I am surprised it is that long. They would probably really prefer 3 years, so that cars are thrown away when the first user has finished the PCP.

Criminal really, because we hear talk about environmental responsiblity in one breath, then throw it away and buy new in the next breath.

Two of my cars have been in use for over 20 years, and the Aston Martin for 10 years. Give a modern car reasonable care, and it will run reliably for far longer that many owners expect.

Not a strategy that motor manufacturers want to encourage though.

[Squaremeal]

As the previous posters have said - Aston1936 did a really good article on this subject:

https://aston1936.com/2018/12/23/the-aston-martin-...

Also, BR did a video about this very subject too

https://www.youtube.com/watch?v=1ViIcOPZqk4&t=...