722.6 Transmission Checking Fluid Level

[Jim2]

When I check the fluid level in the 722.6 5 speed transmission in my w212, the black plastic end on the dipstick "flexes" a little bit when it hits the bottom of the sump. This "Flex" would be between 1/8" and 3/16's " Max 1/4" . So I "juggle" it a little bit to what I think is the correct position. I then fixed a hard rubber washer on the dipstick, right at the top of the metal dipstick tube, so that it cannot go any deeper or "flex". I think that it is now stopping at the correct position in the sump ( At least I hope that it is.... ). My question to the forum is, has anyone ever pushed a different kind of cable or tube down into the sump ( one that will not flex at the end tip, and will stop when reaches the bottom of the sump ) then measured the oil level in inches or Centimeters? I have attached 2 pics to show what I mean. I am really checking the accuracy of the dipstick that I am using, because the fluid level in these transmission's is really critical for good performance, and a flex of a 1/4" is not very accurate. ( BTW, the stick is supplied by Febi Bilstein, so I guess it should be OK .)

 

[HERBIEMERCMAN]

Hello Jim, I have a e-300 td so i think the autobox is the same as yours. I bought the merc dip stick on ebay, from memory i used to get the engine and box up to temperature and with the engine on tick over i would dip the oil level, i do not think the end of the dip stick actually touches the bottom of the sump and there is no bending of the stick at all, the depth it goes into the auto box filler pipe is controlled by the red plastic boss on the dip stick resting on the top lip on the fill pipe. Not sure if your vehicle is exactly the same but hope this info helps. Herbie.

 

[Wighty]

It's not flexing ! That's the flexible dipstick cable that is moving when you push . The blob at the top of the measuring end of the dipstick stops the dipstick at the correct point to measure the fluid .
The black plastic end never touches the base of the sump . (Or at least that's my understanding )

 

[Jim2]

Hello Jim, I have a e-300 td so i think the autobox is the same as yours. I bought the merc dip stick on ebay, from memory i used to get the engine and box up to temperature and with the engine on tick over i would dip the oil level, i do not think the end of the dip stick actually touches the bottom of the sump and there is no bending of the stick at all, the depth it goes into the auto box filler pipe is controlled by the red plastic boss on the dip stick resting on the top lip on the fill pipe. Not sure if your vehicle is exactly the same but hope this info helps. Herbie.

Thanks for your reply Herbiemercman,
The dipstick I have is very long, there is still about 9" exposed when it "bottom's out", and it does not have the "STOP" boss on the end. Which is why I "engineered" a stop on my one. I got a collar used to prevent drill bits going past a certain dept, and locked it on the flexible dip stick that I use on the merc. Its the same transmission i would say as well, the 722.6 one. And I followed the same process as you, warm it up to 80c, handbrake on, put it in "PARK" and dip away.
You got yours from EBAY? Could you check it's length for me, from the plastic tip up to where the metal bit meets the boss? And then it's total length ( inc boss) and I will see if I can get the same one? When you ordered it, were you shown a selection ( by length ), and you selected the one you have now?
What worries me about the one that I have, is that it enters the pipe, ok, passes a "tight "spot, then goes down until it "Bottoms" out, and after that it can move anything up to nearly 1/4 of an inch when pushed.This is the "Flex" I am speaking about.So I withdraw it little by little, and " Tap" it back to what I think is the correct level.
You will see from the pics I posted, that the correct level should read 6 cms. But how trustworthy this is, I don't know. But I believe that the graph showing volume by temperature is correct
Thanks for your help.
Jim.

 

[umblecumbuz]

Wrong dipstick then.
You need the correct dipstick, which - as has been said - stops short of the sump base. It should 'bottom out' at the top, if you get my meaning.
Ebay have them - specifically for the 722.6 gearbox, about £8 from memory.

Engine should be running while in P, and car on level ground.

 

[Wighty]

Thanks for your reply Herbiemercman,
The dipstick I have is very long, there is still about 9" exposed when it "bottom's out", and it does not have the "STOP" boss on the end. Which is why I "engineered" a stop on my one. I got a collar used to prevent drill bits going past a certain dept, and locked it on the flexible dip stick that I use on the merc. Its the same transmission i would say as well, the 722.6 one. And I followed the same process as you, warm it up to 80c, handbrake on, put it in "PARK" and dip away.
You got yours from EBAY? Could you check it's length for me, from the plastic tip up to where the metal bit meets the boss? And then it's total length ( inc boss) and I will see if I can get the same one? When you ordered it, were you shown a selection ( by length ), and you selected the one you have now?
What worries me about the one that I have, is that it enters the pipe, ok, passes a "tight "spot, then goes down until it "Bottoms" out, and after that it can move anything up to nearly 1/4 of an inch when pushed.This is the "Flex" I am speaking about.So I withdraw it little by little, and " Tap" it back to what I think is the correct level.
You will see from the pics I posted, that the correct level should read 6 cms. But how trustworthy this is, I don't know. But I believe that the graph showing volume by temperature is correct
Thanks for your help.
Jim.

eBay special as well .

 

[Yugguy]

If you're anywhere near rugby I have a 5g dipstick I'm unlikely to ever use.

 

[Jim2]

If you're anywhere near rugby I have a 5g dipstick I'm unlikely to ever use.

Thanks very much for your kind offer Yugguy, it's appreciated, but I am in Ireland ( in this case, unfortunately !!! ) But it would help if you could (A) measure it from plastic tip to where the stop is located on the cable, and (B) overall length, plastic tip to top of the stop.

 

[Jim2]

View attachment 48463
eBay special as well .

Thank's Wighty,The proper dipstick is the way to go, so the hunt is on now, as soon as I get the length of the correct one...one I have is obviously too long. Which as you point out, is causing the "Flexing" , But another question ( while we are on the subject... )
For the engine oil dipstick, it does not reach all the way down...it only enters an inch or so into the top of the oil level. I wonder if the transmission is the same set-up, or does the dipstick actually touch the bottom of the trans sump?

 

[Jim2]

It's not flexing ! That's the flexible dipstick cable that is moving when you push . The blob at the top of the measuring end of the dipstick stops the dipstick at the correct point to measure the fluid .
The black plastic end never touches the base of the sump . (Or at least that's my understanding )

You mean the "Diamond" shaped bit at the end of the black plastic, where it joins the shiny flexible silver rod? If this is the case, and the "BLOB" prevents the dipstick ( no matter what flexing ) from going past the correct point, then the oil level that show's would be correct? My problem is that the dipstick is still showing about 9" of overhang after the tip has reached the bottom, which if you are right would not make any difference, None the less, I will get the correct dipstick for that transmission.

 

[Wighty]

Thank's Wighty,The proper dipstick is the way to go, so the hunt is on now, as soon as I get the length of the correct one...one I have is obviously too long. Which as you point out, is causing the "Flexing" , But another question ( while we are on the subject... )
For the engine oil dipstick, it does not reach all the way down...it only enters an inch or so into the top of the oil level. I wonder if the transmission is the same set-up, or does the dipstick actually touch the bottom of the trans sump?

My dispstick was just an eBay one for the 722.6 gearbox . It also hangs out the top of the tube by 9"ish , (but this I believe is because some 5g boxes have different length dipstick tubes (vito ?)
The transmission dipstick stops on that bulge at the top of the 3" plastic section . I would have bourght from MB , but theirs was expensive compared to eBay . When I bourght the eBay one I double checked my current oil level on the car which had not long had an ATF change by MB so I know it reads right

 

[Rory]

You mean the "Diamond" shaped bit at the end of the black plastic, where it joins the shiny flexible silver rod? If this is the case, and the "BLOB" prevents the dipstick ( no matter what flexing ) from going past the correct point, then the oil level that show's would be correct?

Does yours have that 'blob'? The only critical dimension is the tip to the blob, which Wighty has shown. The overall length is irrelevant. Mine is miles longer than the tube.

It's a bit of an art to check the level. I think if you try and do it a few times the tube gets oil in it so the level is hard to read. You're supposed to cycle the selector through each position for a few seconds before checking the level. It needs to be completely hot too.

 

[Oldspanners]

I'm glad to say I have the same problem as Wighty, my dip stick is too long and hangs about 9 inches over the top!
Seriously the plastic part won't touch the bottom of the sump and gives a true reading as I've had no problem (shouldn't have said that) since changing the oil two years ago. it's 7cm from the tip to the neck that stops it going any further.
I also used it for clearing out the water drains at the windscreen.

 

[Wighty]

I'm glad to say I have the same problem as Wighty, my dip stick is too long and hangs about 9 inches over the top!
Seriously the plastic part won't touch the bottom of the sump and gives a true reading as I've had no problem (shouldn't have said that) since changing the oil two years ago. it's 7cm from the tip to the neck that stops it going any further.
I also used it for clearing out the water drains at the windscreen.

Good call on the multi use tool for the windscreen drains buddy

 

[Jim2]

Wrong dipstick then.
You need the correct dipstick, which - as has been said - stops short of the sump base. It should 'bottom out' at the top, if you get my meaning.
Ebay have them - specifically for the 722.6 gearbox, about £8 from memory.

Engine should be running while in P, and car on level ground.

Thanks umblecumbuz. I'm checking Ebay for one now...By any chance do you happen to know what is the correct length I should be looking for? There are several available all supposed to be for the 722.6 box,,,,but they are shown in different length's..

Does yours have that 'blob'? The only critical dimension is the tip to the blob, which Wighty has shown. The overall length is irrelevant. Mine is miles longer than the tube.

It's a bit of an art to check the level. I think if you try and do it a few times the tube gets oil in it so the level is hard to read. You're supposed to cycle the selector through each position for a few seconds before checking the level. It needs to be completely hot too.

Hi Rory, yes I think that it has. See attached pics. Pic 1 shows bulge ( arrowed ) Pic 2 shows plastic on edge, and pic 3 show's jury-rigged "Stop". Is this what you mean? So if the dipstick cannot pass the "Bulge" " Blob" , it does not matter how much is hanging out of the tube? I had driven it more than 50 miles Rory, before I checked it, and it was in "P" with the engine running, did not cycle through it though... will do it next time I'm dipping it.Thanks Jim.

 

[Jim2]

I'm glad to say I have the same problem as Wighty, my dip stick is too long and hangs about 9 inches over the top!
Seriously the plastic part won't touch the bottom of the sump and gives a true reading as I've had no problem (shouldn't have said that) since changing the oil two years ago. it's 7cm from the tip to the neck that stops it going any further.
I also used it for clearing out the water drains at the windscreen.

 

[RhodieBill]

All Dipsticks that are for the ATF Measurement are "Aftermarket". Mercedes does not supply a "Mercedes" Dipstick. (Or if they do they do not sell them - I've tried!).

If you do not have some left sticking out you are using the incorrect length of Dipstick. (They do come in 2 different lengths generally). I find the 1290mm ones to be best - generally.

The ATF should be checked at 80*C - use a Targeting Thermometer on the bottom of the Sump in 6 places and use the average. Anything between 75 & 80 is fine as the Metal exterior of the Sump is open to the cool fresh air so will generally show a lower Temp of a few degrees.

When "Topping-Up" only put about 200ml at a time, and measure on level ground!

 

[Jim2]

All Dipsticks that are for the ATF Measurement are "Aftermarket". Mercedes does not supply a "Mercedes" Dipstick. (Or if they do they do not sell them - I've tried!).

If you do not have some left sticking out you are using the incorrect length of Dipstick. (They do come in 2 different lengths generally). I find the 1290mm ones to be best - generally.

The ATF should be checked at 80*C - use a Targeting Thermometer on the bottom of the Sump in 6 places and use the average. Anything between 75 & 80 is fine as the Metal exterior of the Sump is open to the cool fresh air so will generally show a lower Temp of a few degrees.

When "Topping-Up" only put about 200ml at a time, and measure on level ground!

Thank's Bill. Yes it was hot enough ( 50 mile drive ) and I drove it straight into the garage, never stopped the engine. Applied handbrake, put selector in "PARK", opened the bonnet, removed engine cover tray and dipstick tube cap. Then dipped the fluid. Was at that point that I noticed that there was a bit of "Flex" movement in the dipstick.....up to nearly 1/4 inch. So given the precise level of ATF needed in those boxe's, I was a bit worried. Hence these posts. BTW, dipstick was supplied by Febi Bilstein, so that part is Ok, I Guess. It's also the 1220 mm stick. But from the answers that I have received here on the Forum ( BIG THANK'S TO YOU ALL !!! ) I think now that the black measuring part can only enter to the correct dept because there is a "STOP" bulge on it, so once the overall length is sufficient, it's not important...everything depends on the 8 cms of plastic. Just in case though, I am going to try to locate the "proper" one, which is 90Cms I think.
Regards, Jim.

 

[John Laidlaw]

All Dipsticks that are for the ATF Measurement are "Aftermarket". Mercedes does not supply a "Mercedes" Dipstick. (Or if they do they do not sell them - I've tried!).

If you do not have some left sticking out you are using the incorrect length of Dipstick. (They do come in 2 different lengths generally). I find the 1290mm ones to be best - generally.

The ATF should be checked at 80*C - use a Targeting Thermometer on the bottom of the Sump in 6 places and use the average. Anything between 75 & 80 is fine as the Metal exterior of the Sump is open to the cool fresh air so will generally show a lower Temp of a few degrees.

When "Topping-Up" only put about 200ml at a time, and measure on level ground!

When I had my 230 MB Grangemouth we’re prepared to sell me a dip stick surprisingly but they wanted near £100 for it!
eBay it was but I was lucky as I got the right length ( now with LK)

 

[umblecumbuz]

Don't agree with what's been said above.

How often have you come across an engine oil dipstick that has a few inches left floating at the top when you've inserted it?
Dipsticks made for engine oil level checking are all designed to read correctly when inserted to a predetermined stop. - ie. fully home. That's the only certain and foolproof way of measuring the correct level.

No autobox dipstick (sorry Rodders) that when inserted into the tube has a bit left dangling out at the top can be as certain as one of the correct length that sits 'home' when inserted. There will always be a degree of user variation and uncertainty if the dipstick does not go right 'home'.