bobterry99

My forum comments are generally limited to technical issues or providing an alternate viewpoint to opinions expressed by others to promote diversity in opinion. In 4000+ posts between two websites I don't remember ever commenting on the look of another member's car. But the white-metallic SL600 is stunning beyond belief -- at least it appears that way to me in the photo posted.

When the '02-'08 SL was in production a British car magazine named it the world's most beautiful car currently in production.

FxFormat

That's my 600, it's wrapped in a Satin white pearl, the sun hits it at a low angle making it look like that.

In brighter light, it looks like this



When the red sun sets, it gives off this pearl..i love the color, it never looks the same.

Rudeney

Martin, "MAVA" is very experience, but I am not sure he has a experience with all the details of the 722.9. It had three major problems: (1) Dirty fluid, (2) conductor plate issues and (3) fluid pump bearing issues.

The dirty fluid issue was due to the friction plates used in the torque converter. They first tried to change the shape of the pan to direct more fluid into the filter, but then realized that the early torque converter were going to :"lough-off" some friction material early in their lives. Because of this, they issue a TSB for an initial 40K mile fluid and filter service. As far as I know, this was never corrected and the 772.9 transmissions are now indicated to have a fluid and filter change every 40K miles.

The conductor plate problem is the same old thing that plagued the 772.6 The plate warps and/or cracks and the speed sensors cannot get a proper signal. A new conductor plate fixes the problem. This was not fully resolved until after the MY2007 build. Some speculation is that the old conductor plates were still in production into MY2008.

The fluid pump bearing is less of an issues. The original bearing used, like the 722.6, was a sleeve style. For some reason, that tended to wear more in the 722.9 and became noisy. I am not sure when it was changed, but it was revised to a needle/roller bearing that is better. The symptoms of a bad sleeve bearing are a whining noise at idle or low RPM. It's really just a noise, and may never cause a problem, but who wants a noisy car? I am not sure when the bearing was revised, but I have heard it was nit until MY2009 or even later.

As for these issues, the most serious is the conductor plate. It is pretty much a dealer-only job dues to SCN coding, and will cost around $1500, but it is a permanent fix for the problem. Like I said, the bearing is just noisy, and by the time it fails, you will have well gotten your money's worth from the car. The fluid change on the 722.9 is less convenient than on the 722.6 and other "traditional" automatic transmissions. It has no dipstick, so it has to be force-fed through the drain plug, and the level is checked by the flow rate from the drain plug. It's very do-able as a DIY if you can lift the car high enough to work underneath while keeping the pan level.

For me, none of these are deal-killers, but they are good things to know before jumping into a purchase decision. Your future happiness with your decisions is based solely on your current expectations.

bobterry99

Fair enough. At what mileage might an owner expect the bearing to develop such wear that it would become noisy to the detriment of the owner's enjoyment of the vehicle? At what mileage might it fail completely and require replacement? Has anyone on any forum reported an issue with the bearing?

The answer to the above is material to me. I regard the '07-'08 SL550 as the Holy Grail of normally-aspirated R230s. And as mentioned in a prior post of mine, I am in the market for one. If you were to reply to me that I could expect a minimum of 100K miles from the bearing and I were to purchase a low-mileage R230, then premature failure would simply be a non-issue for me, as I would expect to never come close to approaching 100K.

Rudeney

I've seen noisy bearing on cars with 60K miles, and silent bearings on cars with 100K. It just starts out as an extra bit of noise with the car idling and then just gets progressively worse. You'll find that if you rev the engine, instead of enjoying a nice V8 growl, it gets overshadowed by bearing whine. I will almost sound like supercharger whine, but comes form the bell housing. When it gets bad enough, the torque converter will be allowed to wobble enough that it wears the seal and you'll get a a leak. A lot of shops will just replace the seal, which is easily done with the transmission separate from the engine. But it will likely fail again very soon. It can also cause the gear in the pump to wobble and chew into the bell housing surface. There are aftermarket plates that can be used to fix that instead of buying a new bell housing. The best repair is to replace it with the revised pump that uses needle or roller bearing.

Here is a photo of a worn sleeve bearing. The dark spots are the wear marks:

bobterry99

This is unhelpful, but I sincerely appreciate your reply. I suppose you have insufficient data to form a judgement and wisely made none.

I searched this and another R230 forum for "sleeve bearing". The number of posts mentioning authored by someone other than yourself number just one, and it was made by MAVA. Based upon those two searches, the sleeve bearing seems to have been a non-issue for forum members.

My remain undaunted in my search for a late '07 or '08 SL550.

Thanks again, Rodney.

Rudeney

Yeah, I think it's not really a big issue, but when it starts getting noisy, it is annoying. When I was working in an office building, there were two W211's in the parking lot that made this noise. I approached both owners and discussed it. They were not "car guys" and would take theirs to the dealer for everything. One told me that his started making the noise right out of warranty and the dealer told him (of course) that the whole transmission had to be replaced. The other said his car had about 80K miles and had been doing it for a year or so. He also had the dealer tell him he needed a new transmission, but he went to a local indy who knew exactly what it was and quoted him a price, but also explained that it was "just a noise". so he just didn't worry about it - he'd turn the radio louder.

As is typical, my local dealer won't crack open a transmission. All they do is replace the whole thing. We have two good indy shops here. One of them is owned by an Porsche mechanic who hates MBZ transmissions and won't touch them. In fact, a friend took his E420 there with a 2-3 and 3-4 "flare" and they told him the entire transmission needed to be replaced. He brought it to me and I fixed it with a $6.47 return spring on the pressure valve. I didn't even have to drop the valve body to get to it.

There are some transmission shops and ATRA that post YouTube videos about this. Many don't seem to fully understand the problem (sleeve bearing failure) and blame it on "debris". One supposition seems to be that the sleeve bearing is good for normal driving, but if you frequently drive "spiritedly" at high RPMs, the oil in the torque converter heats up and damages the sleeve bearing. I don't know when it was revised, but the original part number, A1402700197 with the sleeve bearing was changed to A7222700197 with the needle/roller bearing.

Here's a video I found that shows the damage possible:


One error in his narration is that he says the housing is aluminum, but on the 722.9, it's magnesium and VERY expensive to replace. He mentions metal debris as the possible cause, but then goes on to to mention that the bearing failure caused the torque converter hub to wobble.

Keep in mind that MBZ knows what is going on here, but they are not talking. They sold the 722.6 and early 722/9's as "sealed for life". These type of failures on 722.9's caused them to require a one-time 40K mile fluid and filter change. They continued to find issues, so they revise that to EVERY 40K miles. Whenever you see "smoke" (revised service schedules and parts) there is "fire" (a manufacturer's defect).

CorAegean

Rudeney

There is only one pulsation dampener. There are three "accumulators", one for the front axle and one for the rear and one in the middle. This is a good resource for explaining these parts:

http://mercedes-abc-drive-carefully.blogspot.com/

bobterry99

The MY2007 revision to ABC engineered some of the cost out of the system, and that included eliminating the "return" accumulator which had been part of the rear valve block. So, the revised system has a pulsation dampener on the pump and two accumulators: one on each valve block.

Rudeney

Thanks for the clarification on that!

CorAegean

bobterry99

As an aside, why are you interjecting your ride issue into a discussion of SL55 vs. SL550? Had you not considered starting your own topic?

To your issue, with a reasonably-good understanding of the workings of ABC comes the logical conclusion that accumulators can not contribute to a hard ride. Moreover, according to Mercedes' diagnostic software ("DAS"), failed accumulators cause a soft ride.

You have no tell-tale warnings that would result from a failed accumulator. I suggest you leave your ABC system alone and look at your tires and inflation pressures.

850csi

So, just as an update from me, I've pretty much decided on an SL55. So at this point just pretty much keeping my eye on 2005-2008 models (ideally would like 2007-08 but might be more than I would like to spend) at less than ~80k miles. Not in any huge rush at this point, just trying to scope out a good deal...

Rudeney

Be patient. It too me over a year to find my SL. These are low production cars, so there just aren't a huge number to choose from.

CorAegean

danaw007