New member - query about C5 auto box oil change

[rmunns]

I have bought a 2009 C5 tourer exclusive 2litre diesel 165hp. It has 130000 miles on it. I want to change the oil in the 6speed auto gearbox, after being told this should be done. The car has little history - no paperwork covering last 3 years. I try to do car jobs myself, although I do appreciate that repairs are not as straightforward as they used to be. How can I find out which oil to buy, how many litres? Is there a filter fitted to catch debris - if so, should that also be changed? Can this job be done reasonably easily? Special precautions? Easy to get out all of the old oil? Any electronics to fiddle with? Someone told me I might need to reset something in the ECU, although I can't for the life of me think why. Any help would be greatly appreciated.

[GiveMeABreak]

First thing, welcome to the Forum.

Next, post up your VIN - as I don't believe the engine capacity you've quoted is correct for a 2009 year model and it will also help determine which version of gearbox you have. There is plenty on hear about changing the oil - and yes with these modern cars and their computer systems, they do sometimes need to be told what you've done. In the case of your gearbox, it will likely need to be recalibrated once the oil has been changed. Although these are 'sealed for life', most of the auto owning members do change it to support longevity of the box and correct operation. So once we have your VIN, I can see what's what.

[rmunns]

Thank you, Marc. My VIN is VF7**************[VIN obfuscated, can be read by forum staff]********

[myglaren]

As a matter of interest and of great practical value if you want to get into the guts of the autobox, read Jim's stripdown and rebuild account - it's the ZH 4HP20 stripdown link in the menu on the left.

Note the requirement for the correct ATF - critical!

Welcome to the FCF

[GiveMeABreak]

Bear in mind that is for the ZH 4HP20 box Steve, this is an X7 so will be an AM6, but there are 2 versions.

Roger - I've shut down my systems for the night so will get some info to you in the morning.

[myglaren]

Bear in mind that is for the ZH 4HP20 box Steve, this is an X7 so will be an AM6, but there are 2 versions.

Roger - I've shut down my systems for the night so will get some info to you in the morning.

True, Obi Wan Kejimmy. I felt the background info to be relevant though.

[Stickyfinger]

HI
and welcome


As noted, there will be A VERY specific oil for these gearboxes dependant on which model Sub number..

Here is the complete build record for your car, let me know when you have downloaded it and I will delete the file to save space.

http://www.mediafire.com/file/g74c8qn7v ... 1_0151.pdf

[GiveMeABreak]

True, Obi Wan Kejimmy. I felt the background info to be relevant though

A New Year, a new Avatar! Had my Ready Brek today Steve.

[myglaren]

[GiveMeABreak]

Thank you, Marc. My VIN is VF7**************[VIN obfuscated, can be read by forum staff]********

Ok, well there are 2 operations that you will need to do if changing the oil on an AM6 gearbox yourself:

• Undertake the adaptation programming procedure of the oil pressure solenoid valves and regulators
• Reset the oil usage counter to zero.

The procedure is listed within Lexia / Diagbox - the software used for diagnosing problems and technical operations, so I wouldn't attempt this without having access to one.
Draining:

• The gearbox must be drained when the oil is hot (60° C minimum) to eliminate impurities that are suspended in the oil.
• You can only do a partial oil change as you can't fully drain the converter.

If you are raising the vehicle off the ground on a lift with the wheels suspended freely - ALWAYS remove the LDS suspension fluid reservoir cap first and only replace the cap once the car is lowered back to the ground. Not doing this can cause pressure in the system that can burst your LDS tank and has happened to others.

• Remove the protective under engine Panel and the top up plug using a Torx socket
• Remove the oil overflow and drain plug using a 6-sided wrench
• Approximately 3 litres of oil should flow out.

Refilling

• Refit the oil overflow and drainage plug (use a new seal)
• Refit the top-up plug using the Torx socket wrench

So you have a 7 litre dry capacity, 4 litres remaining after you have drained 3 litres, so replace with 3 litres.

• Refit Filler plug and a new seal
  Using a Lexia / Diagbox, Initialise the used oil counter and follow the procedure.

Regarding oil - be very careful - according to the specs, you have the Euro 5 Engine, which should mean that you need the AW-1 oil - a lower viscosity oil (6mm2s at 100 °C).

Some oils on the market will state they are both JWS3309 and AW-1 compatible which are of a higher viscosity of about 7.8 - 8mm2s. This is not the correct one for the Euro 5 Engine Models with the AM6, which need the lower viscosity oil as previously mentioned in the preceding paragraph.

Check your engine, you should find that there is a symbol on the engine that shows 'JWS3309' with a big cross on it to indicate NOT to use this spec. oil. If this is the case you should be fine with the one I've linked to below:
I have located this one that is £8.95 per litre.
http://www.opieoils.co.uk/p-92316-g-for ... fluid.aspx
Now, as you can only replace 3 litres at a time, some people drive around for a month and then repeat the operation again - and for a third time the month after to ensure the bulk of the oil is replaced. You can always get a quote from Citroen for the job if this is a bit daunting - some have been pleasantly surprised!

[rmunns]

Thanks, Marc.

I'll get a price from my dealer.

[rmunns]

Marc, I really want to thank you properly for your reply. It was a bit rude of me to put on such a cursory response to the work you had put in to explain. To do the procedure as you explain will not be possible for me; I am of the old school, quite able to carry out mechanical repairs, but not sufficiently au fait with electronics and car manufacturers' cunning ways of making nearly all work 'dealer only'. I should really explain why I feel the oil change might be needed - I sometimes get a short shreek noise when gently accelerating and also the gearchange can sometimes be slow-ish. It can't of course be superfast, like the Passat I had, but, then, that had a twin-clutch and was essentially a pre-selecting box. I just sometimes have to hang back on the accelerator and 'give the box time to sort itself out'. Are there any more noticeable things to watch out for before getting the work done?

[milleplod]

My C5 autobox is exactly the same in that it sometimes seems to need a second or two to work out exactly what its supposed to be doing. I can predict when its going to happen though....at a particular local junction, for example, where I'll be approaching on a closed throttle, slight downhill incline....I take a view, its clear....foot on accelerator....and wait for the box to have a good old think about things! Of course, its only a second or two, but feels like an eternity!

The interesting thing is that our previous automatic cars all did exactly the same sort of thing at the very same junction - Rover 75/SAAB 9-5 Aero/Lexus IS250/Mercedes R500. None of these were of an age or mileage where the box was (over)due a service, and each box was, I believe, from a different manufacturer to the C5. I know the C5 box has some sort of inclinometer input, as it holds a lower gear when I'm going downhill - all the others did that too. The 'wait' for a response mentioned above is as if the box can't quite work out under all the circumstances whether I'm going to boot it or progress more gently....will I want to keep that low gear, or will a higher one do?!

I'm hoping to get my fluid changed very soon, but I'm not convinced it will fix the 'problem' above, I suspect it'll do the same thing afterwards.....but from a gearbox longevity point of view, the new fluid will be a good thing!

Pete

[GiveMeABreak]

Marc, I really want to thank you properly for your reply. It was a bit rude of me to put on such a cursory response to the work you had put in to explain.

No problem Roger.
Roger / Pete - These AM6 boxes are made by Aisin and are fitted to a lot of vehicles - you can read up a bit about them here - https://en.wikipedia.org/wiki/AWTF-80_SC
So I would expect the behaviour to be somewhat similar. They do have an auto-adaptive feature, so after changing the oil - the service notes do say to go out and do a test ensuring frequent changing of gears so that the ECU adaptive laws can be applied to the gearbox. This will ensure that the quality of gear changing is obtained. I would expect a main dealer to do this via a road test if they are doing the job - but knowing this, I would go out and give the box a good workout through all the gears myself too.

[C5_Jack]

Whit regards to changing the gear box oil
Is there a guide somewhere on here?
Do we know how much oil is required?

Cheers

Jack