ebceksl

I need your help!

Change the transmission fluid in a Mercedes-Benz 722.9 7G plus transmission (S550 4Matic - 2015 short wheelbase)

The oil pan is mounted with six tork bolts.
How to remove the two rear bolt (blue on pic) without remove the rear engine/transmission mount (red on pic)?

The rear engine/transmission mount is covering the tork bolts.


How to remove the two rear bolt (blue on pic) without remove the rear engine/transmission mount (red on pic)?


Best regards,
Erik

Minh

The answer for your question is not possible

DjaKRAbb

Hmm, skip to 8:52 on this video for a 2008 he has removes the 'mount' for the plastic body panels
in your picture, is the 'mount' for the plastic body panels whats blocking your access?

What's the VIN?#

ebceksl

Thanks for your reply.

No it's not the 'mount' for the plastic body panel that is the problem, that kan be removed easyely.

It's the rear engine/transmission mount (marked red on pic) that is covering the torks bolts.
Mine is covering the bolts more than in the video.
(bad angle on my pic?)

DjaKRAbb

can you not just do this? @ 2:44 :

ebceksl

My VIN is WDD2220851A153678, I have the auxiliary pump, but that is located in the other end of the oil pan. The "problem" bolts are in the read end of the oil pan.

DjaKRAbb

Thanks, i was looking at the correct WIS document, and it does not mention anything about trans/engine mounts.. can you not fit an 8mm flat ratchet on the bolt like the youtube video above?

*i uploaded the wis to show you theres no mention of 'major' work -- just have to find an 8mm ring spanner that reaches those bolts

ebceksl

Thank you, yes that might work!

Only problem will be to torque it to 4nm when re-reinstall.

Nice Ride

Also, in the video they do not show you that you can pop in the fill tube to drain the pan better before removal. You can re-install after. NOTE: Mercedes made a change of the fill Tube, there are 2 types that hold different amounts of fluid, Make sure you re-use the original or purchase the correct one. You should follow the directions closely with bringing the transmission to the proper temperature to finish the job properly.

DjaKRAbb

The wis doesnt have the trans pan torque but ... 4nm? isnt it always 8 or 9 for these pans?

ebceksl

Thank you for the advice.
I have the green fill tube. That should be the correct one, and Mercedes original fluid 236.15. I have ICARSOFT Mercedes diagnostic tool to read the transmission oil temperature.

Nice Ride

Don't forget, you are leaving many quarts of old dirty fluid still in the torque converter. Depending on the year, there is a drain bolt on the converter to properly drain most of the fluid out. Also some videos on youtube showing how to flush the converter and the transmission cooler.
Straight forward for pan drop and filter for the most part, but... you are leaving almost 50% of old fluid

ebceksl

Thanks again for the advice. l'm planning to do that, have a new drain bolt for torque converter.

ebceksl

I think the drain bolt for the torque converter is behind this rubber cover?

MBNUT1

Sorry for the off-topic question but the image above shows both internal and external drive headed bolts. What is the rational for choosing one over the other?

Edit: After doing a little research it sounds like it is largely driven by wrench access.

Nice Ride

If you can, post photos of the job. Note: Some converters do not have a drain plug.

ebceksl

Yes I have two questions.
1: The 2 rear bolts on gearbox oil pan (marked blue) are not accessible from under. Maybe they can be removed with a small wrench, but how to install them again and torque them to 4 nm + 180 degree?

2. To drain the oil in the torque converter i believe that the start/stop oil pump (marked red) need to be remove to access the converter drain plug.

DjaKRAbb

You have 4? bolts to 'feel' what 4nm + 180 is (if thats correct).. how many turns after its finger tight etc im sure you can do it by feel is this car on a lift? or jacks? im impressed with the lighting also

ebceksl

You are right, I have 4 bolt to get the "feeling" for 4 nm. It should be possible.

Yes the light is great! I have access to Scania's workshop via my son.

DjaKRAbb

Amazing

Ah so that explains why its in the WIS document... ill have a look for those instructions for you

DjaKRAbb

I assume you understand swedish . goodluck

chassis

Delete

DjaKRAbb

The WIS in post #7 has , step 4, remove aux pump, step 5, drain TC

chassis

Quite right, I stand corrected. Some variants of the 722.9 do not specify torque converter drain.

DjaKRAbb

WIS for my 722.6 doesn't specify the TC to be drained so i was a little confused seeing it here. Theres a variant of the 722.9 that you have to remove the rear cross member (what he didnt want to remove to get at those 2 bolts) to fill it also, i hope OP doesn't have that one