Dirty oil in 722,6 auto box

[See elle Kay]

I have a 99 clk320 that has a gear shift problem.

How do I ensure to get the most amount of oil from the transmission? I removed the drain plug but only a litre or two drained out. I then removed the drain plug from the torque converter, which contained 2-3ltrs or so. I estimate a total of 5 1/2 ltrs drained out of the transmission in total.
Is there more oil somewhere? Should the gear lever be in a certain position? Have I missed something?.

i changed the transmission plug. The old one was quite soiled with oil.

id like to get the most oil out because the old oil is very dark brown/orange. Not confident that it had ever been changed. 180k km on the clock.

i wasn’t going to change the valve body plate, maybe I should.

some advice on how to get the rest of the oil out would be a great help. Thank you in advance.

mike

 

[EmilysDad]

I'd imagine there's a filter in the sump ... I'd clean/replace that rather than worry too much about whether you've left any ATF in there. Not all torque converters have a drain plug so a partial ATF is the best they can do.

 

[robin.large]

You should drop the sump on the box, change filter and clean out any sludge. You have drained all the oil you will get. Clean oil at the correct level makes a difference.

Sent from my KB2000 using Tapatalk

 

[Jim2]

As above re.dropping the sump and replacing the filter. There is also some fluid in the trans cooling radiator and feed pipes. But it is a little complicated to replace this oil. You have to disconnect one of the pipes, ( I use the one on the drivers side, coming back from the radiator to the transmission) with the engine running, and the trans in P, pump out 2 litres and stop. Refill 2 litres of new fluid, and repeat until you see the new fluid emerging. Its important to monitor exactly how much fluid comes out, and after refilling the trans, to check the level at 80c. I would not be even thinking about replacing the valve plate at this stage.

 

[mioba]

You also have to replace the sump gasket.

Make sure the sump is wiped clean.

Refill it. there are markings for hot and cold readings.

Only way to totally flush is use a specialist who use a device by literally flushing from
inlet to outlet.

Best bet, drop the sump, lots of screws. replace filter, clean sump with tissue/brake cleaner, reinstall,
Refill to the correct level - must be spot on. Go for a drive. Remove sump nut, drain what you can and refill.

A million and one vids on youtube.

 

[See elle Kay]

Thanks for all the reply’s.
I removed the trans sump, very slimy! No magnet? Which I thought would be in there. No metal fragments just very dirty. So new filter and gasket will go on later and I will top back up.

if I do decide to undo the banjo bolt that goes to the trans cooler to drain that oil. Does the trans cooler get refilled from the dipstick or is there another orifice?

 

[EmilysDad]

...... Does the trans cooler get refilled from the dipstick or is there another orifice?

If you're lucky enough to have a dip-stick (generally missing from cars theses days) I'd just fill it from the dip-stick tube. Cars these days often have a fill/level plug or some kind of overflow tube within the drain plug

 

[Wighty]

Thanks for all the reply’s.
I removed the trans sump, very slimy! No magnet? Which I thought would be in there. No metal fragments just very dirty. So new filter and gasket will go on later and I will top back up.

if I do decide to undo the banjo bolt that goes to the trans cooler to drain that oil. Does the trans cooler get refilled from the dipstick or is there another orifice?

Yes fill from the dipstick tube , it fills the cooler,torque converter and sump .
When you measure the atf oil with the dipstick it must be when the gearbox oil is hot . Measure the level with the engine running , on a flat surface and with the gearbox in P .

 

[Oldspanners]

Thanks for all the reply’s.
I removed the trans sump, very slimy! No magnet? Which I thought would be in there. No metal fragments just very dirty. So new filter and gasket will go on later and I will top back up.

if I do decide to undo the banjo bolt that goes to the trans cooler to drain that oil. Does the trans cooler get refilled from the dipstick or is there another orifice?

Using the banjo bolt on the drivers side is the way to do it. The most difficult part is getting a piece of tubing to fit tightly over it, I ended up using a piece of heat shrink and a hose clips.
My advice is to take the sump off again clean it, fit a new filter and magnet refill and then start the flush from the banjo bolt. In total I used about 10 liters to end up with clean oil coming out. Have bottles clearly marked at 2 liter intervals so as you can stop the engine and refill via the dipstick. When clean oil flows put the bolt back on noting how the washers fit, check the level, run it up to temperature and adjust as necessary. This way all the oil in the system has been changed and hopefully restore the box to full working order.

 

[EmilysDad]

..... . Measure the level with the engine running , on a flat surface and with the gearbox in P .

.... after cycling through the gears

 

[Wighty]

.... after cycling through the gears

You know it buddy

 

[RhodieBill]

Just to add from what the others above have said:

For a start you should have got at least 2.5lts from the Sump using the Drain Plug. (And then about another 500Ml by removing the Sump and Filter).
Stating that you got only 1 to 2 could have well caused your "shift problems"....

Personally I would have just Tested the Level before doing all you did, and topping up if required to the correct Level.
Then, Drained the Sump, removed the Sump itself and replaced the Filter and the Rubber Seal on the Sump making sure to keep all the ATF in one clean container then measuring it exactly as much as possible. Then fill the Sump using the Dipstick Tube with the same amount of Fresh ATF, followed by a Road Test.
Depending on the results of the Road Test, you then take further action. (If required).

 

[Jim2]

For connecting the fluid return to a length of plastic piping, I bought a longer banjo bolt, and fitted the hose to it using a clip. No problem with oil running all over the place then, as its under pressure.
All the other points (Car level, and in P, drain / replace 2 x 2 ltrs, cycle through the gears etc) have been covered in the previous posts, but one other thing under no circumstances use any form of micro fibre cloths whil on this job. Auto Transmissions hate micro fibres.
Good Luck, and let us know how you get on, or if you have problem.

 

[Oldspanners]

For connecting the fluid return to a length of plastic piping, I bought a longer banjo bolt, and fitted the hose to it using a clip. No problem with oil running all over the place then, as its under pressure.
All the other points (Car level, and in P, drain / replace 2 x 2 ltrs, cycle through the gears etc) have been covered in the previous posts, but one other thing under no circumstances use any form of micro fibre cloths whil on this job. Auto Transmissions hate micro fibres.
Good Luck, and let us know how you get on, or if you have problem.

For connecting the fluid return to a length of plastic piping, I bought a longer banjo bolt, and fitted the hose to it using a clip.
Wish I'd thought of that

 

[See elle Kay]

Thanks again for all the advice.

this car is in a bit of a state. We have um and arrhh’d about spending 15-20k on another car or restoring this one. Better the devil you know and all that. And after all when it’s working right, well it’s a lovely drive. We don’t have to go mad, it’s old and not the most practical for us, but if we get good safe enjoyable motoring for the next 4yrs then that’s awesome.

i guess I was a little hasty in draining the oil. I had dipped it cold and there was a little oil on the end of the stick. I think for now. I am going to settle for the new filter etc and fill up with the same qty that came out. Leave what’s in the cooler for now. Get it running and up to temp, so that once the level is good I can road test to see if it shifts better. From there I can make a plan.
Once the car drives again I will start with a full service.

once mechanical jobs are done we will look at the respray, head lining and seat repairs. Oh and new stereo, oh and fix the leaking boot, oh and the boot release, and polishing the headlights and and......

 

[EmilysDad]

..... and fill up with the same qty that came out. ....

Fill it to the mark on the dip stick It seems that it could have been a little on the low side before you started

 

[Wighty]

I think the sump holds about 3.5L , so as @EmilysDad says it was well low to start with

 

[Jim2]

Fill it to the mark on the dip stick It seems that it could have been a little on the low side before you started

Yes, personally when I drained mine, I saved all that came out, and replaced that at the minimum, and then checked and topped up. When you are draining the TC and cooling rad + feed / return pipes, it will always take extra due to flushing out the old fluid. Took me 12 ltrs to do mine, but I let it run a bit even after the new fluid appeared to be on the safe side.
For the planned change on the 220 722.9, I've got all the gear together. 20 ltr blue fluid, Filter, Gasket etc, but this time, the TC can be drained manually as it has a drain plug, you just have to remove the electric pump and turn the engine until the drain stud appears. For the rad and pipes, I'm not too sure at the moment. The set up looks slightly different tha it is in the 722.6. so I'm not too sure if the Banjo bolt will work this time. But I have a fluid pipe taken from the steering rack of a 2016 Peogeot 508, and the fittings look remarkably the same as whats on the connection between the MB cooling pipes and the transmission body. We will see how it goes.....I have no more excuses for not getting it done.

 

[Jim2]

Thanks again for all the advice.

this car is in a bit of a state. We have um and arrhh’d about spending 15-20k on another car or restoring this one. Better the devil you know and all that. And after all when it’s working right, well it’s a lovely drive. We don’t have to go mad, it’s old and not the most practical for us, but if we get good safe enjoyable motoring for the next 4yrs then that’s awesome.

i guess I was a little hasty in draining the oil. I had dipped it cold and there was a little oil on the end of the stick. I think for now. I am going to settle for the new filter etc and fill up with the same qty that came out. Leave what’s in the cooler for now. Get it running and up to temp, so that once the level is good I can road test to see if it shifts better. From there I can make a plan.
Once the car drives again I will start with a full service.

once mechanical jobs are done we will look at the respray, head lining and seat repairs. Oh and new stereo, oh and fix the leaking boot, oh and the boot release, and polishing the headlights and and......

Well leaving the rad and pipes out will make the job a lot simpler, it wont be as good as a full change, but from the way you are describing it, anything wil be a big improvement on what its like at the moment. At least you were lucky that you could get the TC done,,,,,thats a big PLUS. At a later stage, you could do a simple change from the sump, and then top it up wilth fresh fluid......all the time you will be reducing the concentration of old fluid. There are several forum members who change the oil and filter, but not the TC or the radiator / pipes etc as the TC does not have any drain stud, and has to be drained at the same time and method as the rad change. Instead, they do frequent changes via the sumo stud, same as engine oil change, and over time the concentration of fresh fluid gets greater.

 

[See elle Kay]

This was the old oil. 4ltr in total I have put 4 back and run the engine and checked, nothing on the stick. Box not warm to the touch either.
I’m going to leave it running then keep checking and topping up as necessary. I’ve shifted through the gears, which seems more responsive already.