R230 MB SL550 722.9 Transmission removal tips

[apostle]

Anyone here have info on how to remove the 722.9 transmission out of a 2007 SL 550. I suspect my torque converter is on its way out as the car seems to shudder on occasion at low rpm (1000-2000) and noticed the tach oscillates when cruising between 1200 and 1700 RPM. Otherwise seems to work. No lights or codes.

Also can this be done on the floor or do I need to get a lift too?

 

[Petrol Pete]

Hello and welcome along .Based on this you are going to remove the whole transmission ??? Have you had the transmission serviced recently ? Most everything on this transmission can be got to from below by just removing the sump.

More detail on the service history of this gearbox please. We can go from there.

 

[apostle]

Figured as much. As for service history, just got the car, so not sure what was done. Was planning to change the filters, pan and fluids though, before coming the realization that this potential issue is there.

Does the tach bounce also point to an issue with the torque converter? Note: I don't think it does that in cruise control, but will need to verify.

 

[merc85]

Tacho bounce can also be the conductor plate playing up.

 

[Jobsworth]

You won’t get the tc out just by removing the sump!
It isn’t a massive job to drop the transmission out complete, but bear in mind it is heavy. Surprisingly heavy. If replacing the tc I recommend standing the gearbox (with an assistant) on its tail, and dropping the new tc down vertically. You must ensure it goes fully home into the bellhousing. If you don’t it will shear the oil pump drive tabs, and that’s a whole box strip to replace. If I had a pound for everytime I had to replace an oil pump because another mechanic had messed up fitting a torque converter to a 722.x transmission I’d have, well, about eight quid, but you get my point...

tach bounce can be a sign of tc failure, but in my experience a light vibe, akin to crossing a cattle grid just after a gearchange is the most common symptom

 

[Petrol Pete]

Jobsworth , we all know you can't get the torque converter out through the sump , my answer to OP post was to get to the bottom of why he thought he needed to remove the torque converter.

It would be a dull forum if someone on their 2nd post asked how to replace the crankshaft on their 2019 C63 and none of us asked why? But simply showed them how...

 

[Jobsworth]

Jobsworth , we all know you can't get the torque converter out through the sump , my answer to OP post was to get to the bottom of why he thought he needed to remove the torque converter.

It would be a dull forum if someone on their 2nd post asked how to replace the crankshaft on their 2019 C63 and none of us asked why? But simply showed them how...

The OP asked a question about removing the gearbox on an R230. Asking him why he wants to do that comes across as slightly patronising to me. I’ve offered advice on how to do what he asked, and then talked about my experience of the symptoms I’ve encountered with torque converter problems so he can come back to tell us what he’s experienced with his car.

I’m wondering if you have a problem with me. A while back I can remember you ridiculing me when I mentioned spark plug indexing on direct injection mb engines. You went a bit quiet when I linked you an official document detailing the proceedure and its importance. I’m not here to pick a fight. I own a German car specialist garage, and enjoy sharing the experience I’ve built in over thirty years working on Mercedes Benz motor cars. I’ll happily bugger off if you don’t like me

 

[apostle]

Appreciate the responses. I'm going to wait and see how this progressives before I start tearing this down. Maybe its just me getting used to an automatic and this is all fine.

 

[219]

Figured as much. As for service history, just got the car, so not sure what was done. Was planning to change the filters, pan and fluids though, before coming the realization that this potential issue is there.

Does the tach bounce also point to an issue with the torque converter? Note: I don't think it does that in cruise control, but will need to verify.

When you say you just got the car , was it a private sale , or did you buy from a dealer/trader ?

If the latter , you would be entitled to take it back to them and ask for this issue to be fixed , or they might prefer to give you a refund .

I don’t know specifically with that model , but with other MBs I’ve had , the easiest way was to take the engine/gearbox out with a crane if working at home .

 

[apostle]

Got it from a private person in April and unfortunately did not detect this issue during the test drive in the street. Problem seem to be worse with low amount of acceleration like highway cruising. Going to check transmission fluid condition and level tomorrow. Maybe this is just low fluid level.

If I need a new transmission ok - but want to exhaust other options first.

Should I risk a partial transmission fluid change?

 

[W1ghty]

Got it from a private person in April and unfortunately did not detect this issue during the test drive in the street. Problem seem to be worse with low amount of acceleration like highway cruising. Going to check transmission fluid condition and level tomorrow. Maybe this is just low fluid level.

If I need a new transmission ok - but want to exhaust other options first.

Should I risk a partial transmission fluid change?

How many miles on the car ?
Do you have service receipts that show where the car was serviced ? Mercedes dealers will have records of the cars service and repair history that will list gearbox atf/filter if it was done

 

[MarkPortugal]

I have a different model to the OP, these are general tips for transmission removal at home with minimum tooling.

Transmission removal tips;
Jack up the car as high as you can, set it on 4 good jackstands.
I'm assuming that anyone with a lift doesn't need tips...
Disconnect the battery.
Remove everything that's in the way. Exhaust system, cross member [that holds up the tail], drive shaft, clutch slave cylinder [if you can, otherwise remove the tube and let it drain into a container], electric connections, shift linkage, starter motor, etc.
Let the transmission hang down, and you should be able to see the top bell housing bolts. Those are the tough ones.
Use a ratchet wrench with a very long extension, a cross joint [universal joint] and suitable socket.
Wrap some tape around the U-joint so it's flexible but not floppy. You should be able to reach it in there and get it onto the top bolt.

When the bolts are all out, a wide plank across the car below the transmission, supported from both sides works well for those of us working at home without a transmission jack.
When you pull the transmission back, it will settle onto the plank.
After it's free of the engine, the plank can be lowered one end at a time to safely and easily lower the transmission to the floor.

Mark Holden
Portugal