Hello everyone, I’ve got a question that I just can’t seem to find a reliable answer to anywhere. How much oil exactly does a completely empty Powershift 6DCT450 (after a full rebuild) take? I’ve read in several places that the gearbox along with the cooling system holds about 7.5 litres, while some sources say it’s 8. However, the garage that will (maybe) fixing my gearbox claims that I should fill it with about 9.5 litres. What do you think about this?

7 hours ago, iantt said:

 

Thank you very much! I understand this is a snap from an official Ford service manual? So, does that mean I should avoid that garage at all costs? 🙂

The garage is allowing extra as the fill procedure can entail putting in more than it holds, excess drains back out. I wouldn't worry over couple of litres. 

But they claim they'll pour in 9.3 litres and seal the gearbox, meaning they'll leave 9.3 litres in the system

Filling from completely dry sounds about right

So, to sum up, in a closed system, should this gearbox hold 9.3 litres or 7.5? 🙂

7.5 will be the refill capacity I'm guessing.lots of areas that when draining won't drain fully. So possible 9.5 could be about right completely dry

 

47 minutes ago, iantt said:

7.5 will be the refill capacity I'm guessing.lots of areas that when draining won't drain fully. So possible 9.5 could be about right completely dry

Alright, now I'm totally confused 😅 I found this website: https://drivelineap.com.au/2020/04/27/getrag-6dct450-470-dual-clutch-transmission/

and if I understand correctly, according to them, the full system holds 7.5 litres, and about 5.5 litres drain out during a service.

From that first image you sent, it also seems like the gearbox comes pre-filled to capacity, and you’re only supposed to check the level, not fill it with an additional 2 litres. If the system held 9.5 litres, the information in that manual would be very misleading, I think. 🤔

I suggest there is some confusion here.

You would certainly NOT just "fill it" with an amount of oil and seal it up. There is no "level plug" as such - this is misleading as the control chamber won't be full.

"9.5 litres and box it up" says, to me that I'd avoid anyone saying that?

The correct procedure in this case would be, IMHO (pretty much as per @iantt screenshot)

Fill from the filler hole until oil comes out of the plug on the side (again, this is NOT  a level plug!)

If you are certain it is completely dry I'd add 1 litre (to accommodate cooler and pipes if they have been drained) AND  make sure the filter was filled before starting. A bit of overfill at this stage shouldn't harm as you are then going to go through the level check procedure.

Then run it to prime everything - place lever in each position for about 20 sec (I believe this ensures solenoids are flushed and primed) Also get fluid up to some temperature that isn't in the Ford manual I have.

Once you've done that, go through the checking of the level process:
Open side plug, collect what drains out and measure.
Add oil in 250ml increments until it flows out of the side plug.

When this flow drops to a dribble, refit the plug.

I add about 50-100ml to allow for leaks on an older box.

You can find the level after your initial refill using:

Recalculation of the old transmission fluid level: 
Using the measuring container, add the escaping transmission fluid to the before collected transmission fluid. 
Collected transmission fluid – filled transmission fluid = old transmission fluid level (e.g. if 300 ml (250 ml + 50 ml = 300ml) have been collected and 2x 250 ml have been filled into the transmission, would mean that the old transmission fluid level was 200 ml (300ml - 500 ml = -200 ml) to low). 

I think Alan gets it right even though he calls it a level bung!:
https://www.youtube.com/watch?v=CERqRSK2SWM&t=393s

How does that sound?

 

Thank you so much @Shearers, this clears up a lot and gives me a much better view on it! So, it’s definitely time to look for another garage.

However, there’s still the question of how much oil is actually there 😅 I’m sorry to keep asking, but this is more of a technical issue now—the garage is absolutely certain that the system must hold exactly 9.5 litres, which seems a very high value to me. Yes, this isn’t the best garage, and they don’t specialise exclusively in Powershifts, but they have been repairing various automatic gearboxes for a few years.

Perhaps there’s someone who repairs these gearboxes or works in a Ford service who could provide a precise answer? There has to be a correct value, even an approximate one 🙂

 Ok, it looks like I (maybe) found the answer. In the tech guide published by ATSG, it states that 'full fill - 7.5 litres (8 qt) (including the cooler)',which matches the information @iantt provided earlier.

https://atsgbookstore.com/getrag-dct-450-tech-guide-dl/

The same information is mentioned at 45:40 in this video (also ATSG): 

So, an extra 2 litres could probably damage the gearbox.

If any of you have experience with this publisher and know that their manuals contain errors, I’d appreciate hearing about it 🙂

I agree with that ATSG estimate, they seem to be a reliable source and anyway, it doesn't really matter if you put a bit more or less on the initial fill as you are going to run at idle to circulate the oil and then go into the checking of the level procedure which will mean that you end up with the correct level.

I use this kit:
https://www.ebay.co.uk/itm/112436788478

It is 7l and although I have never filled it from "dry" there is usually at least 1l left over for top ups/level checking each year. If you had an extra litre, that should be more than enough?

If any fluid comes out and is collected cleanly, it can be re-used.

I can't see how any garage insisting on filing with 9.5l as the only thing to be done, can understand this transmission?

Therefore I'd want a detailed discussion with them about their expertise in this entire matter and certainly check their understanding and acceptance of the level check procedure.
If they won't accept what you have found out here and with your researches and want to "fill it up" I'd find another repairer?

I'm tempted to ask what the problems with the gearbox are and again, check that any workshop has good expertise in this type of transmission?

 

Classic problem: bits of plastic in the oil and clogged solenoids. Even though the gearbox is working pretty well, it really needs to be stripped down before those bits cause any real trouble.

So, I asked how they check the oil level. Their answer? They... pour the oil in through the side hole, start the engine, and then check if the level’s good (using the same hole). Now that I’ve read up a bit more on this gearbox, I’ve got one thing to say… Actually, maybe I’ll keep that to myself 🙂 

To be fair, I picked this garage because they offered a competitive price and didn’t have any bad reviews. Maybe they’re good with standard automatics and are just starting to learn Powershift? Anyway, I’ve already found another garage that’s been doing nothing but Powershifts for over a decade, even though the price is more than twice as high 🤐

Based on other threads on this site, the standard of "transmission experts" seems very low/variable.
Our local experts offer what I view as a good warranty (which is crucial IMHO):
https://austrin-engineering.co.uk/services/
If done right, it should last a LOT longer (which we'd probably do for our 2011) a poor job may last days or weeks before problems reappear - hopefully, paying a fair price will mean a quality job - can they point you to customers that have had work done?
I'd expect to be involved and get photos, perhaps, and detailed reports on what is found and done but that's me?

On 1/17/2025 at 7:24 PM, Shearers said:

Based on other threads on this site, the standard of "transmission experts" seems very low/variable.

It’s actually really hard to find a good garage. At one, which came highly recommended, I was told they simply pour in 8.5 litres and consider it fine...
Out of curiosity, I wrote to ATSG to ask if the value in their manual is correct. I’m quite interested to see if they respond 😉

No wonder rebuilt gearboxes fail after just a few dozen thousand miles (or even less) when workshops can’t handle something as basic as filling the oil to the manufacturer’s specs.