Hey all, recently my 2002 E55 started pouring ATF, I immediately though TCU connector and ordered one. Well during replacement, I saw fluid coming from the bell housing so I ordered a new oil pump seal. During that job, I found this:





It appears that the welds at the snout of the TC have broken! Has anyone experienced anything like this? Currently, I am searching for a replacement TC and would appreciate any leads before I order through the dealer.

My friend who does transmissions gets all his tc's from TCS A local company here.
You may want to look into finding something similar around where you are.
He also has a special lube he adds before instal. I will get the name later tonight when I am over there replacing the leaking plug on my trans and cleaning up the computer.

I'd need to see it in person but I'd call the weld good. What you are seeing is " rotary friction welding " weld flash from the hub and converter cover. One way to test is get a piece of rad hose and some fittings then rig things up to pressurize the converter ( 10 pis is plenty to find a leak with soap )

Hubs can be MIG welded on a fixture or friction welded. Rotary friction welding is where one part is held and the other is rotated, as heat builds the parts are pressed harder together then finally rotation stops and the parts are pressed at an even higher pressure. The machine looks like a metal lathe.

Friction welding is fast and effective on a large scale, but not the kind of thing a converter rebuilder will have. ( I'm specing out a new one at work , pricing is upwards of $ 750,000. )

Your real problem is the pump bushing has failed, look at the two brass lines on the hub. Also look at the galling next to the pump drive slots on the hub. I wonder of the front pump had broken drive tangs at some point and a set of gears was dropped in at some point to get things going again.

When the pump bushing has excessive clearance, the seal rides off center and the increased fluid leakage past the bushing can overwhelm the seal. On some trans ( GM ) it can actually blow the seal out of the pump housing.

I think, that the 722.6 trans needs an alignment tool ( that looks like a converter hub ) to center the pump when the halves are taken apart. If this is the case and that tool was not used, it will cause a pump miss alignment.

To answer your question. I would use a CVC torque converter. It has the updates for cold weather. They are about $200 with a core. Get them at Whatever It Takes.

Torque Converters Distributors Page - Consolidated Vehicle Converters, Remanufacturing Torque Converters for Automatic Transmissions

I use them for all my 722.6 torque converters on all my rebuilds. I do S600/S500's

How many miles on the clock?

I would inspect the front of the bell housing where the pump mates-up. Should not be pitted/ scratched..

What engine does the E55 have?

I'd replace the rear stater bushing bearing. The front bearing can be replaced instead of buying the expensive pump. Sonnax makes the bearings for these 722.6's

Rear Pump Stator Bushing - 68915-01 - Sonnax

Pump Bushing - 68004-01 - Sonnax

How far have you gone into the transmission?

Martin

Here's a couple more pictures





You can see the affected area if you look closely at the inside

Did you read any of my post 3?

The car currently has 196,xxx miles on it. The w210 e55 has the n/a 5.4 v8 engine. And I doubt any trans work has been performed in the past. The oe lock on the fill tube was still present when I started with all this. I haven't gotten into the trans at all.

When it comes to those Sonnax bushings, is there a DIY for replacement?

Here is what I would do if I were in your shoes...

Weather you like it or not. You will into the first half of the transmission, and i would replace the frictions, and put new seals. Size-up the frictions to the correct gap, but really for your mileage, and what your about to do. It is a no-brainer to rebuild this your self. The 722.6 is easiest to do first DIY tranny rebuild. You would be $300 or so into the rebuild kit, and $50 into one bonded piston. Oh, $50 bucks into the the front bearings.

I'm going to rebuild my E320 4Matic at 180kmiles as my rear engine seal is leaking.

I have not done a DIY on this as I have 800 or so pictures from one rebuild showing blow by blow.

I have all the literature and pictures, and it would fit on a 16gig thumb drive if you want it. Just mail me a thumb drive, and I can load all the info..

A friend is going through the rebuild, and the service manuals are up on the site here on this thread. I think it is on Post 36

722.6 slip and shudder in D and R, rattly noise in N and P problem on 1998 S420. - Mercedes-Benz Forum



Notice, the last picture on post 27 is the front of where the pump mates-up. Mine has a few little pits on left and right, but I have seen them very pitted...

Hope it helps,

Martin

I'll be taking you up on that offer, Martin. At this point, would you also replace the torque converter due to the damage and scarring on the snout?

First where do you reside? in the USA?

Yes, you want to replace your torque converter no mater(scored or not-just mileage I would replace it) what you do... Even if you buy a used tranny. The reason is on the 722.6 and 722.9(same torque converter) it is has frictions in it and they just wear-out..

Those bushing bearings are a must too in your case...

On any rebuild of 722.6. The must is:

A) torque converter
B) bonded piston
c) front pump bushing
D) rear stator bushing
E) Rubber seals/teflon seals(in rebuild kit)
F) All frictions replaced(all sized to appropriate gap of .7mm to 2mm depending on the spec for the clutch pack)
G) circular external connector replaced

This is a very easy transmission to rebuild

My opinion 200k is the limit on this transmission before hard mechanical damage occurs..Not that the whole thing wears out at the same, but the lower gear frictions just wear out faster because we are just on them more, and they are at the back of the transmission.

Martin

I'm from South Carolina but currently in California for the holidays.

You should have brought it to California in your luggage as we could have rebuilt it in two days...

MArtin

Where in California are you located?

@97 SL320 I read your post and see what you are saying. The bushings you spoke of, is there a DIY for replacement? And is it required to dismantle the trans to do so?