04 XC70 Transmission Service Required - where to start?

[mikeamondo]

Just did the first of 3 drain and refills.... the oil was Filthy, with a capital F. Not anything like that lovely lavender color that showed up on the dipstick, which I getting better at pulling without burning my hands.... Also, I drained 4.25 liters out, so I only put 3.3 back in and took her for a 20 mile drive. Just got back and checked the levels, at it's till showing overfilled but not nearly as bad. On the next drain, after lunch, I'll refill .5 liter less than I drain and it should be about right.

Also... I ran my shop magnet thru the oil and picked up a few metal shavings. Not bunches... like 2 or 3 little slivers... Is that to be expected or not?

[Georgeandkira]

Depends how big the slivers were.
It sounds like you're a candidate for 3 more D&F's; possibly more; or possibly a pump out.
I like to get the fluid to look like it's AT LEAST responding to D&F's before a 12-14 qt. pump out.
Remember, a filthy transmission will pump out to clear red then soil the fluid again as the TC cleans.
Guessing when to do D&F's vs. a pump out for the fullest benefit is simply a judgement call.

I recommend Wolf'sHead "Super Universal Synthetic Transmission Fluid" from the Amaliestore.com as they ship the stuff for free.
I've used it on 3 different AW55-50 units and it's great stuff.

Man, I ALWAYS tell people that a smear of trannie fluid on a wipe rag NEVER looks as bad as the fluid is.
An initial D&F will tell a lot and it's not all that wasteful if the fluid comes out cleanish.
Get 'er clean.

[precopster]

Never seen fluid replacement fix anything related to codes.

You have communication issues you need to concentrate on by removing ECM/TCM and cleaning sockets as well as removal and cleaning of the sockets close to the air cleaner I previously mentioned.

[mikeamondo]

No worries..... sometime it takes more than once for me anyway. I'll work on removing those boxes and cleaning the contacts. I already have the tool and I pulled one before during a previous saga with this car. I took out one... ECM I think, but I couldn't get the other one out. Seemed like the tool would not seat properly to release it, as I recall. The contacts were clean on the one I took out, but the car sat mostly unused for about 2 years since that time.

Now, we have some new clues.... took the car on a hundred mile drive today and saw at least 3 more events. I haven't checked the codes yet, but here are the new symptoms.... AC started blowing warm, as the fuel press gauge and tach stopped working. Transmission again was not shifting correctly. Brake failure warning came on the dash the first time, but after a restart, it went away. At each occurrence the situation would correct itself after a few minutes... AC would suddenly blow cold and gauges would start working just fine, correct shifting would resume. All instantly, and at the same time. After the 3rd event, the dash message showed 'Engine System Service Required'.
I know I need to do another Vida DICE scan, which I will... but right now, I'm quite tired. That will have to wait until tomorrow sometime. Also, I'll take a stab at removing and cleaning the contacts. Should I be seeing visible corrosion and dirt if that's the culprit?
Thanks for your continued help... I'll be digging into the communication issues next!

[precopster]

You don't really see surface corrosion as the pins are small and sitting vertically from our line of sight.

This is beginning to sound more and more like a CEM failure if the contact issues at ECM/TCM aren't the problem.

The largest CEM connector can also be the culprit.

[mikeamondo]

I found some threads on CEM overheating issues with MY04's .... the failures were much more extreme than mine, but certainly similar. They describe full shut downs on the interstate, lights coming on and off, door open, etc... really crazy stuff. Hoping that means mine may just be corrosion at the plug or something else. I'll do some research today on how to get to it and check for corrosion / etc. And, of course, I'll the tcm and ecm and clean the contacts. If the CEM Connector is problematic, is that another part that needs cleaned, or is it to be replaced? In other words, does it corrode or just fail for some other reason?

[mikeamondo]

Oh... also... what's the recommended brand of contact cleaner? Preferably something I can buy locally instead of having it shipped....
Thanks!

[precopster]

There are brands 2 brands I know of. They both use the same solvent base. I use CABAC or CRC.

[mikeamondo]

So... tonight I pulled both the ECM and TCM, and scrubbed the pins with a tooth brush and contact cleaner. They didn't look corroded, but who knows. I added some dilectric grease and reinstalled. Then I tried to take the CEM out to clean the large plug, but I couldn't figure out how to get it to release. The one video I found showed the guy reaching up while he says ' just push on the bracket ' and pull forward on the CEM... he does this and the CEM pulls right forward easy peasy.... Yeah, well mine didn't do that. I pushed on the bracket and pulled on the CEM until I thought it might break in half.... How does it come out? Is it supposed to be hard to pull?

After it became obvious I needed more input on the CEM, I took the car for a nice 12 mile drive with no issues. This means nothing of course, but tomorrow we'll take her in to town and put her thru some paces... supposed to be in the 90's so it should be a good test.

[bugeye]

Our 2004 XC70 had CEM problems. Sent to XeMODeX. Quick turn around and no further issues in 4 years, 35,000 miles. As I recall, the CEM is squeezed between the bracket ear. Push the ear and the CEM twists free. Just hard to access and see. Brut force not required.