Gearbox Fluid Change

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jimmy

MB Enthusiast
Joined
Aug 8, 2002
Messages
2,316
Location
Northamptonshire
Car
Discovery 3 TDV6, Discovery 300TDi - Plaything!
After talking to George Fraser at the GTG I have decided to change my auto gearbox fluid. I ordered the parts from my local stealer.

Measuring Stick
Sump Gasket
Gearbox filter
Gearbox Fluid

The total bill was less than £40.

However! They insisted I will only need 3 litres of ATF fluid, I reckon it will need more than this? Haynes say 5.5litres.

Can anyone check this please? I dont want to drain the fluid and not have enough to refill it.
 
Is this the discrepency George talked of between changing just the gearbox oil and changing the torque converter oil as well?
 
the torque convertor will hold the remaining fluid - so if you just drain the gearbox you will only get 3 litres out.

I don't know if your gearbox/torque convertor drains are the same as a W124 but if so they both have separate plugs.

The gearbox one is easy to locate - on the side of the sump, the torque convertor one less so. Look at the bell housing from below and at the point where it joins the block you should see a small rectangular inspection hole (it may or may not have a plastic cover clipped in to it) measuring about 3" x 1.5" looking up through that hole you can see the edge of the torque convertor, get a friend to slowly spin the engine using a spanner on the crankshaft pulley until you see the drain plug go straight past the inspection hole :) then do it again only a little slower :) (on the petrol engines it's easier with the plugs out to take away compression but it can be done with them in) Once you've got it lined up remove the plug with an allen bolt and there's the remaing couple of litres of ATF fluid all over your arms face and driveway:) A bowl to attempt to catch this fluid is possibly the most useless addtion to your tool kit as all it does is blocks your view of the allen bolt.

HTH

Andy
 
Yep, my torque converter sounds/looks the same with a drain plug in it. I told the guy I wanted to change ALL the ATF fluid including the torque converter!!:devil:

Looks like I will be getting another 3 litres in the morning. Sounds like their idea of changing the fluid is just the sump and not the torque converter too.

To me there is no point in changing just the sump fluid as the fluid in the torque converter will contaminate the rest!!

The last thing I want is the car on the ramp, with the gearbox half filled on a bank holiday weekend.
 
Hiya Jimmy,
Ive been considering doing my auto box oil for a while but am not sure what the recommended mileage is for changing it. Let me know how you get on with doing it, also have you got the part numbers for the bits you had to buy ?
 
I have just done the fluid change, and it takes 5.5 litres.;)

I checked in the Autodata book and that said 5.5L the same as the haynes manual. I was lucky to get to the stealer just before they shut on my way home and pick up another 3 litres.

The job is easy enough, I did it as soon as I got home so that the fluid and gearbox was still hot. The hardest part was turning the engine to get the torque converter drain plug at the bottom, a 1"1/16 socket on the end of the crankshaft makes it easier.

I have some photo's, the filter is a very strange looking thing, it looks like a wing mirror.

To be honest I was shocked at the state of the old fluid, I don't know how MB can claim that will last for the life of gearbox, unless they hope the gearbox wont last long!!:devil: The new fluid is like cherryade but thicker, the old oil was dark brown and very smelly!!

The torque converter holds more fluid than the actual gearbox and when I removed the sump, you could see tiny bits of metal on the surface :eek: looked like metallic paint. Cleaned it all up and re-assembled and filled with genuine MB ATF fluid. Took it for a test drive and it has made a big difference to the gearchanging of the box, much smoother than before.

I can recommend anybody doing this job, it is relatively easy but I wouldnt do it without a ramp. Total cost for parts was about £65. If you do decide to do it ONLY USE GENUINE MB ATF FLUID, DO NOT USE ANYTHING ELSE!!!!
 
GEARBOX OIL CHANGE

Mercedes say the gearbox oil should be changed every 72000mls on my 1992 300D.

I had mine changed a few weeks ago, and as I'm not a very good DIYer I took it to a local Auto gearbox specialist who's been there donkeys years.

He charged me 70 something pounds to change it including filters gaskets etc. I watched him do it and I'm glad I took it to him, my driveway would have been awash in gear oil if I would have attempted it. You definately need a ramp, and watch it when you take the oil plug off, the oil on mine gushed out everywhere, this guy had one of those oil collectors under it so was OK.

It only took him 5 minutes, it would have took me 5 days.


bob2.jpg


Bob
 
Originally posted by jimmy
I have just done the fluid change, and it takes 5.5 litres.;)

I checked in the Autodata book and that said 5.5L the same as the haynes manual. I was lucky to get to the stealer just before they shut on my way home and pick up another 3 litres.

To be honest I was shocked at the state of the old fluid, I don't know how MB can claim that will last for the life of gearbox, unless they hope the gearbox wont last long!!:devil: The new fluid is like cherryade but thicker, the old oil was dark brown and very smelly!!

The torque converter holds more fluid than the actual gearbox and when I removed the sump, you could see tiny bits of metal on the surface :eek: looked like metallic paint. Cleaned it all up and re-assembled and filled with genuine MB ATF fluid. Took it for a test drive and it has made a big difference to the gearchanging of the box, much smoother than before.

If you do decide to do it ONLY USE GENUINE MB ATF FLUID, DO NOT USE ANYTHING ELSE!!!!

Jimmy

I echo your findings having changed my ATF some while ago. Are you sure about the quantity of fluid. My car was underfilled at 6 litres and took a while for the converter to transmit drive properly, so I went back to the dealer and they checked the quantity and said it should be 7.5 L for the 722.6 5 speed box. I added more and the level came up.

Did you get a dipstick ok?
 
Originally posted by Dieselman
Jimmy

I echo your findings having changed my ATF some while ago. Are you sure about the quantity of fluid. My car was underfilled at 6 litres and took a while for the converter to transmit drive properly, so I went back to the dealer and they checked the quantity and said it should be 7.5 L for the 722.6 5 speed box. I added more and the level came up.

Did you get a dipstick ok?

Yes I managed to get a 'measuring stick' as they call it. There are 2 marks, one lower mark for 25'C and an upper one for 80'C. I have put in just under 6 litres and think I am slightly over the mark. Will check tonight as soon as I get home whilst it is hot to get a proper measurement.
 
Don't forget to have the engine running and cycle the selector through all the gears and back to P. Keep the engine running whilst taking the reading or fluid drains back from the torque converter.
 
Jimmy

I've checked my dipstick and there are two marks at the top and two marks at the bottom. Each pair of marks indicates min and max levels for the oil at the appropriate temperature.

I think yuo need to add more oil to bring the oil up to the 80 degree marks with the gearbox hot.
 
Dieselman,

I checked the level when hot, in P with the engine running and I had to add another 1.5Litres, so the total capacity was 7.5litres.

Thanks for your help, much appreciated.
 
What about changing the gear box oil on a petrol 2.4 engine, has anyone who has changed theres noticed a significant difference.
 
Originally posted by n3thn
What about changing the gear box oil on a petrol 2.4 engine, has anyone who has changed theres noticed a significant difference.

I had George Fraser change my autobox oil when the car was at approx 60k miles. The gear changes were noticeably better (smoother). George also commented that the oil looked like it needed changing.

To be honest, the biggest effect on gear changes was when I had a faulty MAS replaced recently, the car is really silky smooth now and just ever so slightly brash if driven really hard when the engine is stone cold first thing in the morning.

S.
 
Originally posted by n3thn
What about changing the gear box oil on a petrol 2.4 engine, has anyone who has changed theres noticed a significant difference.

It would be the same gearbox so the procedure and results would be the same.

There is a debate on if the gearbox fluid should be changed or not. MB say not as the gearbox is filled for life, but then they might be expecting/hoping for a shorter life so that they can sell replacement gearboxes and charge for fitting them.

Basic maintenance says that fluids should be changed. The fluid that was in mine was dirty and smelt 'burnt' if you get what I mean. The gearchanges are definetly a bit smoother, it depends on if you think it is worth paying £200 or thereabouts for a garage to do it or if you are prepared to have a go yourself. To be honest I wouldnt fancy doing this job without the use of a ramp.
 

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