Hello everybody,
There has been a lot of chatter about the CVT gearbox. I have had a go at collating the information available and carried out a fluid change. Rather than write it all here I've attached (I hope) a pdf document. I hope readers find it enlightening and any feed back would be very welcome.
I would especially like people to let me know if they have a suspect car and how they're getting on, good or bad.

Document revised to cmax4a.pdf 20th September 2010, please see later post below.

Pavillion.

Hello all.

Many thanks Pavillion for this really helpful information and for the photos you have forwarded to me.

My C-Max came up with the transmission failure warning light after 46000 miles and has been with specialist Derek King (The Mechanical Workshop) since January. See Honest John website for details. Derek has traced the problem either to a fault with the speed sensor or with the PCM to which it is connected. Ford will not supply either component and has offered 25% off the cost of a replacement transmission. My local Ford dealer has not even replied to my request as to whether it is prepared to PX or buy back the car, before or after a replacement transmission on the terms proposed by Ford.

In my case, Derek has inspected the speed sensor and found it to be clean, without the gunk noticed by Pavillion. He therefore has doubts whether the kind of service carried out by Pavillion will solve the problem. He's going to look into Pavillion's information in more detail and come back to me next week.

I'm not satisfied with Ford's offer, very dissatisfied with my Ford dealer and considering legal action. If any others with unresolved C-Max CVT problems are interested in taking this further, please contact me via details on Honest John website.

Reg

This is a revised and updated version of the article I have wriiten.
Pavillion.

[quote name='Pavillion' timestamp='1285004215' post='98029']
This is a revised and updated version of the article I have wriiten.
Pavillion.
[/quote]

Many thanks Pavillion fr sharing your experience.

I'll try to find a dealer here in Portugal that could take the same care you had on changing the gearbox oil, as mine C-Max auto is now with 6 years (79.000 km). I just bought it to its first and unique owner untill now.

I like the car, but this subject on the CVT is taking my attention.

Hi
My Cmax 04 1.6 Auto gearbox failed last week and would not drive in any gear, after leaving the car overnight every thing worked perfectly. I took the car to my Ford dealer who told me it would probably need a new box, but to carry on running the car until it stops.
This did not seem the right answer to me so I searched the web and found your Pdf file. I would like to try changing the oil in the box as it has done 70K miles and the problem seems to have been an electrical glitch. ( I Hope!)
Could you tell me where you obtained the parts and the approximate costs.

Using your Pdf info, I have found from Automatic Choice the following:-
Lubegard CVT Fluid Lube 23
Filter CFT23.FIL01
Gasket CFT23.GAS01
Did you use these or use Ford parts.
I have noticed they also supply a Gasket CFT23.GAS02 for a non ZF box. Do you know if you can tell its a ZF box before removing the sump.

[quote name='alkazam' timestamp='1296259407' post='111657']
Hi
My Cmax 04 1.6 Auto gearbox failed last week and would not drive in any gear, after leaving the car overnight every thing worked perfectly. I took the car to my Ford dealer who told me it would probably need a new box, but to carry on running the car until it stops.
This did not seem the right answer to me so I searched the web and found your Pdf file. I would like to try changing the oil in the box as it has done 70K miles and the problem seems to have been an electrical glitch. ( I Hope!)
Could you tell me where you obtained the parts and the approximate costs.

Using your Pdf info, I have found from Automatic Choice the following:-
Lubegard CVT Fluid Lube 23
Filter CFT23.FIL01
Gasket CFT23.GAS01
Did you use these or use Ford parts.
I have noticed they also supply a Gasket CFT23.GAS02 for a non ZF box. Do you know if you can tell its a ZF box before removing the sump.
[/quote]

Hi
I have just bt an 04 c-max with a faulty CVT23 box (stupid me -should have read up first). Same symptoms - does not drive and Transmission Failure showing. My diagnostic tester shows a number of faults which I am looking at. Just wondered how you got on. Did you get the fluid from Automaticchoice or somewhere else as ford insisted on selling me 75w90! for the car. If so did changing the fluid help?
Cheers

Sorry to hear of your problems with the Cmax.

When my box stopped working the transmission failure message appeared. After leaving the car overnight the box worked again and the message disappeared.

I do not know why the box failed it could have been electrical or maybe a blockage in an oil way.

I changed the oil and filter in the gearbox sump and found a small amount of fine metal filings stuck to the magnets so I was sure there was no serious mechanical problems.

I replaced the oil using:-
Fuchs TITAN ATF CVT High-Performance Automatic Transmission Fluid from OpieOils.co.uk
This has the correct Ford Spec.

I have now covered another 2500 miles without any problems.

The oil change obviously can't repair a failed sensor or mechanical component but I now have confidence in my car again after completing the work.

Alkazam.

[quote name='alkazam' timestamp='1300572441' post='119180']
Sorry to hear of your problems with the Cmax.

When my box stopped working the transmission failure message appeared. After leaving the car overnight the box worked again and the message disappeared.

I do not know why the box failed it could have been electrical or maybe a blockage in an oil way.

I changed the oil and filter in the gearbox sump and found a small amount of fine metal filings stuck to the magnets so I was sure there was no serious mechanical problems.

I replaced the oil using:-
Fuchs TITAN ATF CVT High-Performance Automatic Transmission Fluid from OpieOils.co.uk
This has the correct Ford Spec.

I have now covered another 2500 miles without any problems.

The oil change obviously can't repair a failed sensor or mechanical component but I now have confidence in my car again after completing the work.

Alkazam.
[/quote]

Thanks Alkazam
I have now checked it and the fault indicating sensor failure has cleared. There are no rough noises when running or turning the wheels and it seems to change gear ok. There is no drive (haven't tried much because of damaging the pump) and several DTC's (low pressure etc) because there is no fluid in it so I will have a go at replacing the fluid and see what happens. Trouble is I am told it needs 9 ltrs which for lubguard will cost £140! What did your fluid cost and what colour was it? . The reason I ask is I suspect someone may have put ordinary auto trans fluid in as it is red (Lubguard is yellow). Also, does anyone on here know how to get all the fluid out as I am told there will be lots left in the torque converter etc. I suppose I should do a flush really but will try it first and if it runs can always flush / change again afterwards. If anyone has a u/s gearbox (or u/s sensor) I would be interested in buying it as I am sure I could remanufacture the sensors for them as I work with instrument sensors.

Edit:
- Alkazam thank to your tip for opie oils - just saved me nearly £70! AND I got 10 ltrs instead of 9 - They had a 25% off everything this weekend! Thanks!