Hi all!

I posted a while back about an awful droning vibration through the speed range under full torque lockup on mu 1997 E320.

I had the fluid changed at a Merc dealer a few months ago now... and up until yesterday the car has done really well. Droning virtually gone.

Yesterday, the droning returned.

Looking at the invoice, they only changed 3 litres out of the box, instead of the whole amount... (but they did do the filter and seal!). they also told me the tranny was in a good state, no metal lumps in the pan.

Could it be possible that the old oil has tainted the new over the last few months?

I have been looking at the forums here, obviously... and wondered if anyone has had this experience at all? Before you enquire about the radiator - it is not contaminating the transmission fluid with glycol.

The trans shifts perfect, the droning is only felt in full torque lockup under light load. ECU change didnt help either. That was tried too.

Because only 3 litres has been changed, I'm keen to do another change with the proper tools and oil. What is the TOTAL capacity of the 722.6? According to this forum, it varies between 5.5-7.5 litres.

Finally, I'm keen to try this excellent procedure here: http://www.peachparts.com/shopforum/tech-help/148108-atf-change-w210-post1119234.html#post1119234

However, I dont think my 1997 E320 sports that torque converter drain plug. Must have been an option!!!

Thanks for any advice you can give..

Mike F

they didn't drain the convertor, if you don't the fluid will usually get contaminated right away. total drain and refill with filter is around 8 quarts of fluid, but you are well off getting the correct tool for checking the fluid as to not over fill. in a shop environment the way i do it is i add initially 3 quarts start the car then add 3 more while it is running, go for a drive to get the trans up to temp, mercedes says 80 degrees celcius, then check it and add accordingly, at 80 it needs to be at the top of the upper mark on the tool. to get the temp i use the factory mercedes diagnosis computer, but i would think you could use an infra red thermometer on the pan. also since they usually leak, it is a good idea to replace the data plug on the side of the transmission when you do the service

buy:
one filter 140-277-00-95
one gasket 140-271-00-80
one dataplug 203-540-00-53
one magnet 220-271-00-98
8qt mercedes atf
2 seals one for each drain plug 007603-010100

A '97 has the drain plug for the converter. If they didn't do it and you asked them to, I think they ought to do it again and right this time.

Len

drain plugs were omitted from MY2000 and newer, being a 1997 the only way it wouln't have a drain is if at some point after 2000 a new converter was installed. replacement units do not have the plug either

Hi all,

Thanks for your replies. I will look again for TQ drain plug, but if it isn't there - whats the best way to do the job best so my oil doesnt get contaminated again?

whilst we're on the subject of contamination, have you seen many MB cars that have done this, and can better explain why what happens does? IE, the vibration at torque lockup (and not in slip conditions).

Thanks again

Mike

well obviously if the torque converter has the plug drain it replace the filter and all the fluid, if it doesn't have a drain there really isn't much you can do, i think a flush would be fer costly if even an option.

Hi, thanks for that - I asked the question because if the drain plug ISNT there... I'll probably need to do 2-3 changes... and as costly as THAT is, I may not have much choice.

Obviously, the more changes I do the better, but how little "contamination" does it take to ruin the rest of the fluid? It seems to have happened once by changing 3 litres.... next time I'll change more - but there will still be an element of contaminated fluid.

Its almost like a virus... I honestly thought I was cured first time.... and why on earth does it only affect the TQ lockup?

No one seems to have heard of this at MB UK dealerships... on C class rad faiures resulting in similar symptoms (but not the cause in this case)

Thanks

Mike