cmpcpro

Hey guys! I dropped my car off today to get the tranny rebuilt. I was referred to the place by a VERY reputable outfit.. This place doesn't deal with the public but with other shops and MB itself! I spoke to the guy who has been in the business for over 32 years and he explained the reason I've had 4 of these cars and all four have felt the torque converter locking up (though not as bad as this one) is because MB made their converters shafts in aluminum and they become egg shaped and lose pressure. This place has developed a converter with a steel shaft and a very nice seal. Among other mods they say this transmission will shift VERY nice and positive. They also offer a two year unlimited mile warranty!! I'll have it back on Friday and I can't wait!!!


We have researched the various problems associated with Mercedes Benz automatic transmissions and have developed procedures and modifications to avoid premature failure. Our expertise and unique manufacturing processes result in quality, which has allowed us the privilege to earn one of the best reputations in the business. Some of our information has been published in a large transmission repair chain in house technical guide. Our customer base includes all of the major transmission repair franchises, Mercedes Benz Dealerships, Mercedes Benz Classic Center as well as independent repair stations.

Welwynnick

The drive shaft that takes the torque from the engine to the torque converter? Aluminium?! That's very unlikely. it wouldn't take the wear and it wouldn't take the load. Aluminium is used for the casings and some of the clutch baskets and cylinders, but not the drive shafts.

I rebuilt my own transmission a year ago, and am very familiar with it. TC's take real specialists to rebuild - I had my mine rebuilt, but there will only be a handful of people in any one country.

There are no shafts in the TC. The shafts are on the transmission. Perhaps they're talking about something slightly different? Are they talking about the inner guide to the TCC piston?

Nick

cmpcpro

The part that goes onto the shaft of the tranny is aluminum on the converter not talking about the driveshaft

cmpcpro

I can ask them when I pick it up but he said where the converter goes on to the input shaft of the tranny it's made out of aluminum.. their converters that part is cut out and replaced with steel.. I was telling him I grew up with a family who owned dealerships so I would go out and pick which car I wanted to drive and have driven thousands and the four S classes I've owned are the only ones I can really remember always feeling the converter engage even on the one that had 30k on it.. that's when he said MB had had an issue with their converters and this part ovals out like an egg and the seal then stops sealing and you have a pressure loss.. he said their converter with the steel part and their really good seal the problem is resolved and with their other fixes the trans will have a very nice positive shift and that slush box shift I get at high Rpms will be much nicer.

Welwynnick

That sounds like the piston guide. It doesn't transmit any torque, but it does act as a spigot bearing between the transmission & TC/flywheel; guide the TCC piston, and channels the oil to the TCC.

I've heard of lots of TC clutches going bad, but that's often attributed to the tranny valve body instead. That would be a very difficult sort of fault to trouble-shoot. These people must do some very trick work indeed. You have to grind off the TC peripheral weld-line just to get at that part.

Nick

cmpcpro

They were definitely talking about the actual converter but I'll ask again when I pick it up.

GrepAwk

Does your '06 S55 have the 722.6 5-speed?

Let us know how the service goes. And if they are good, it would be nice to have a referral. Where are they located?

cmpcpro

Yes it's the .6 and I will absolutely let you know! I am in Los Angeles and they are local

maw1124

I have dealt with Sun Valley Transmissions out there, and since you're in the area, it might be worth a call to Marc as a check on the information you're receiving. The unit is the same so the information should match. They rebuilt and upgraded my 500E transmission. Excellent work, and service.

They are pretty much the ONLY non-MB go to transmission specialist among enthusiasts for the older collector vehicles.

maw

P.S. I recognize the blurb from their website in your original post. Those are THE guys. A little more information from them for the group, here... http://www.mercedesdismantlers.com/7226.html

cmpcpro

Good job Maw Mark is the guy!

cmpcpro

Got the car back today. Mark showed me the piece they use on their converters and it is NICE! Machined and beautiful.. anyway.. HOLY CRAP!! He told me the stall they use is a little higher but with the 55k it brings it to about 1500 rpm so if you give it a little gas off the line it starts to move at 1500 now vs right off idle but if you give it even a little gas its like the car is being shot out of a rubberband.. by all means the car feels like it has an extra 100hp no joke.. I looked up this thread and they seem to love them too!

https://mbworld.org/forums/w211-amg/...er-review.html

exhaustgases

So is the part your talking about the STATOR SUPPORT?
So is the place that did the part and work Sun valley transmission?
And what is the total cost?

cmpcpro

I'm not sure the name but it's the shaft that goes into the engine from the converter and on the inside the input shaft goes into it. Yes Marc at Sun Valley is the one who did it. I wanted to make sure he was okay with me mentioning him before doing so. Driving the car with a 1500 stall is a little to get used to but the car pulls so freaking hard now it's just unbelieveale.. those guys on that link mentioning that it's the best bang for your buck mod are telling the truth!

Welwynnick

Was it this part?

Nick

cmpcpro

Yes that's it!

maw1124

This is good intel for if I ever need it. Thanks, cmpcpro. I'll certainly talk to Marc about it. Another real bang for the buck mod I've heard of for these is a Wavetrack LSD... http://www.wavetrac.net/application.htm. I didn't dig enough to know if the E55 or SL55 units fit, or what. I'm trying to keep the chucking of AMG bits off the car to a minimum, but for those who are interested...

Cheers,

maw

exhaustgases

Wow and I thought german engineers were supposed to know something. Well in the old days they would have done it properly, now its just kids on computers designing stuff, with not much understanding of how it all works.

cmpcpro

I think I made a mistake on the stall.. car doesn't get going until 1500 so would that make it a 2000-2500rpm stall?

maw1124

Certainly old Mercedes (and tanks, airplanes and boats) built to much more robust applications also had failures. It's usually the petroleum products that go bad (rubber, plastic, seals and gaskets). They simply can't hold up to the heat cycling over the years. Germans are known not to do rubber, plastic and vinyl too well.

maw

Welwynnick

+1000

maw1124

I've found that when I've considered cars to be a collection of a few categories (metal, paint, natural products and petroleum products), it has helped me to understand and deal with what's going on. On garage kept cars with normal use, it's generally not the metal, paint or natural products (wood, leather) that go bad. And when they do, it's generally no big deal. It's the petroleum products that go bad, and for predictable reasons at predictable intervals. This includes fluid petroleum products. So just replace them before they go bad. It's really that simple. The car will last longer than your interest in it.

maw

P.S. By the way, Nick, what's that part you posted?

exhaustgases

I really thought the picture was an aluminum part that SHOULD have been made of steel. And shows that someone does not know the material that should have been used. We the consumers are then stuck with the junky designs. In the old days the only aluminum parts in an automatic transmission where servos and pistons, not driving members with in the transmission. Then of course they wanted to make things cheaper, yeah cheaper should not be in the Mercedes manufacturing manual. Since it is a top dollar car.

maw1124

That's why I asked about the part. My bet is on the center bearing going bad, deforming and what not, letting fluid and/or pressure escape the system. But I take your point about steel vs. aluminum, even though it was probably weight saving as opposed to cost saving, that drove the decision.

maw

Welwynnick

That's the piece that sits on the end of the transmission input shaft, and on the inside of the torque convertor clutch piston, so I describe it as a piston guide, though it does other functions. It doesn't transmit any power, though.

Nick

cmpcpro

What do you mean by doesn't transfer power? That's what connects the converter to the transmission, all the power should be going through it right?