Transmission Oil looks like Mud

[JonathanC]

Hi

A couple of weeks ago I took my 1994 E320 to get it's transmission oil changed as I have just brought the car and do this as a matter of course. The garage duly put the car in the workshop and about an hour later charged me for changing the oil and a new filter. On the way home I didn't notice any difference in the gear changes.

Yesterday I decided to check the oil and discovered it to be over filled. I duly syphoned out about 1/2 litre to bring it down to the Max mark. I was expecting to see nice clear red oil to come out but the oil looks like the colour of mud. The gearbox doesn't have any particular problems (yet). I have done about 1000 miles since having it changed, is there anything that could have caused this in such a short space of time or is it more likely that the oil hasn't really been changed?

Thanks for your help.

 

[mjtray]

The transmission oil should be a nice light red colour....sounds to me like they did not drain the torque convertor which hold a couple of litres of transmission oil.....take the car back and ask them why the oil is still dirty....did they actually change it????????

By the way, the transmission oil should only be checked once the engine and transmission oil is nice and hot and should be checked with the engine idling, otherwise you are likely to get a mis reading.

Cheers

 

[JonathanC]

Thanks mjtray, you are confirming my suspicions - they didn't change the oil. I have since spoken to them and of course they insist they did but could only offer two explanations of why it looks like it does-

big problem in the transmission which I don't believe as it shows no signs of any problems.

radiator leaking into the oil cooler. I assume if this is the case the oil level will go up again and I would see some emulsification in the coolant which I haven't seen. Coolant level is fine to.

I am taking the car to them tomorrow so hopefully they will live up to their reputation and change the oil and filter.

Cheers

 

[pascal]

Have read before about different methods of changing the AT oil.

I have never done it myself, but realize that just draing is no good as, MJ explains above.

I have heard of people pouring in new fluid while engine running, at the same time as draining it from the bottom, till the clear fluid runs through. I do not know of the exact method, so maybe someone else could enlighten.

I think that dealers have special equipment (pump etc) for removing all the old oil.

 

[Myros]

My mechanic lets me watch

He warms it up good and proper, drains it out, then dismantles the pan and gets the rest of it out. Refills with about a litre less than the book volume, tests the dipstick, and comes in with another half-litre. warms it up again and then does the final dip and top-up. The handbook says the level (ona 107) should be about 10mm below low on the dipstick for filling purposes when cold, but I can't work that out myself, as I thought it sat over the top level, and goot dispersed when running!

 

[guydewdney]

If the filter and pan were not replaced, I wouldnt be surprised if it was black / brown imediately

I very recently did a sprinter 4 speed box - the new oil went black very quickly, and I had to take the valve ody apart to fix the problem I had...

The filter holds another 1/4 litre, and the valve body has so many little crevises that it will hold lots of horrible gunk in there.

However - im surprised that you didnt feel any differnce - no slight improvement in gear changes at all??

Guy

 

[jules335500]

Oil changes make no differance to the performance.its noted that auto boxes hate the heat and need changing every 18months etc.£60

 

[JonathanC]

If the filter and pan were not replaced, I wouldnt be surprised if it was black / brown imediately

I very recently did a sprinter 4 speed box - the new oil went black very quickly, and I had to take the valve ody apart to fix the problem I had...

The filter holds another 1/4 litre, and the valve body has so many little crevises that it will hold lots of horrible gunk in there.

However - im surprised that you didnt feel any differnce - no slight improvement in gear changes at all??

Guy

He allegedly changed the filter as well, he even checked that it was OK to do so as he orginally quoted for a filter for a 4 speed and mines a 5 speed. I also asked him to check the adjustment of the control cable. The only differences I noticed when I left was at full throttle the gears changed up at the red line, where previoulsy they changed a little into the red but I guess this could have been the cable poorly adjusted.

I don't want to be unfair but at the same time I don't want to be ripped off. Bearing in mind they should have changed the filter, is it likely I would still have mud coloured fluid after 1000 miles as a result of gunk inthe nooks and crannies?

 

[JonathanC]

UPDATE

I visited the garage today. They inspected the car and and drained off the excess oil but insist that they did change the oil. They claim that the colour of the oil is due to water in the oil, entering through the oil cooler under the radiator. Personally I am not convinced as the oil level and apperance was the same after they changed it as it was before. I don;t know how to take this forward, I can't prove . I think I will change the oil myself and monitor it. If it doesn't look like the current oil after 1000 miles then I will know they didn't change it.

It would be nice to find a garage I could trust to do the job properly for a change.

 

[mjtray]

Can we ask who you used?...I notice you're in Berkshire, as am I. I can recommend a very good Indi who I trust 100%.

I just hope you have'nt just used them, as that would be embarrassing!!!

Cheers

 

[MW]

I can't see why oil should go brown in 1000 miles. Mine will go a little darker after 18K. It should be very strongly red.
I think it is unlikey it was done, or didn't drain the convertor. It is not a difficult job. On my W124 the oil is £12-15, and the filter and gasket £10-12 from Euro Car Parts. Takes about 90 minutes. The Haynes manual is quite good with instructions on how to do it.

 

[JonathanC]

Can we ask who you used?...I notice you're in Berkshire, as am I. I can recommend a very good Indi who I trust 100%.

I just hope you have'nt just used them, as that would be embarrassing!!!

Cheers

Hi MJtray

Until I have managed to prove whether I am being told porkies or not it would be unfair to name and shame, however it isn't anyone in Berks!

I would be interested as to which specialist you use, I have tried one of the Reading/Caversham ones and was not impressed so I hope it is the other!!

The car is due a service and as it has so far a full MB history I am tempted to use Tony Purslow in Basingstoke. I might ask them to change the ATF but I think I will only be convinced after I have done it.

I was hoping that one of the gurus might comment on the likelihood of water entering the oil cooler from the rad, this might be plausible in which case maybe the specialist is telling the truth.

Cheers

 

[tom7035]

Jonathan, have you had a look at the other thread, "Have I been nobbed?" by Squealinneil - Similar to yours regarding contamination, with differences of opinion. (by the way your ATF should be a bright pink colour ideally, and very difficult to see on the dipstick).
Cheers, Tom.