S600 722.6 Trans Pump Noise
 

So I fixed my ABC pulsation damper, technically my daughter did she wanted to install the part and I let her, bout as easy as a part install could be. Good news, the whine is gone from idle up to 2k RPM, bad news, it was masking another noise over 2k RPM which I thought was the higher RPM range for the damper. It wasn't. From what I can tell it's the front oil pump inside the transmission, so step 1 is going to be to change the fluid and trans filter.

The fluid and filter are en route to me, question to you guys would be is anyone interested in pics and whatnot from doing this? I'm not sure how common these jobs are so if anyone wants to see pics when I do it, let me know. Otherwise I won't bother. That said, if the fluid doesn't fix the problem, anyone got any leads on a front oil pump for a 722.6 trans?

Try a national scrapper like LQK!

too much effort. get one from ebay for $1000 or thereabouts, transfer the valvebody and tcu to avoid scn coding and call it a day

When I had my S600 trans replaced, the dealer installed a factory rebuilt unit, which cost $3800. I believe labor to do the trans swap was almost the same cost as the unit.

Tranny swap is under 8 hours job if you don't know what you are doing. Much faster if you have done it before...

I'm not worried about the labor, I'm trying to keep costs down. It looks like the front oil pump is the same for all of the 722.6s. I'd rather not get a used one, my car only has 80k on it and if the pump is failing already I don't have much insurance that a used one won't do the same thing. From what I can tell, the front pump is the same on all the 722.6s so I can get one that fits like a dodge sprinter or an old c-class or whatever and it should fit and work correctly. I'm going to do a tune-up this weekend and see if that fixes the noise, I'm doing oil, air filters, and fluid/filter/gasket for the trans.

Update: Just finished the trans fluid, removed 4qts and changed the filter, the noise is completely gone. Looks like the filter was just clogged, the fluid was pretty gross.
https://cimg8.ibsrv.net/gimg/www.mbw...071c7f0b09.jpg

Moral of the story: Everyone changes their engine oil, but the transmission needs love too.

That is good news. You swapped out probably 1/3 of fluid and given your acumen for fixing stuff from a DIY perspective, the other 2/3 has to bug you given how bad it looked.

Problem is, if filter is clogged, it's clogged with clutch material. Chances of it clogging again are good and/or your clutches are toast.

This fluid does not have a healthy color. Something is going on in your tranny. Prolly clutch material is clogging things. Your flush cleared up things a bit, but I think you might have more serious problems down the road. Find a knowledgeable dealer that can determine clutch wear by observing shifting pressures via xentry to determine if this is the case. If you care that is.

Having taken apart several transmissions with twice this many miles, this is the color of trans fluid that hasn't been changed in a long time. I agree with Mike it's likely it was clogged with clutch material, and it will eventually need a rebuild, but that color coming out of a trans with 80k is totally normal. I also checked for metallic flake, and there was less than I was expecting honestly. The magnet was of course full, but again it's on its original trans fluid, I don't think I've ever seen a magnet come out anywhere near clean at this mileage. I don't claim to be a master at automatic transmissions, but I've seen this color before, a lot.

I'll be changing the fluid another two times to get as much transplanted as possible, but I just drove it a hair over 1,000 miles from NY to VA and back and not a peep. Eventually I'm going to either rebuild it or send it off to Renntech to have them build it stronger (the torque converter is likely going to be failing soon anyways), but today is not that day.

Don't change it twice more. Just once. But remove the valvebody (1.5-2 quarts more will come out) and look for the torque converter drain plug (the hole is behind an oval rubber plug on the bottom- turn engine until drain screw is visible) and get the rest 2.5-3 quarts out.

The later 772.6 didn't have a TC drain plug. Grrrrrrr.

Nick

I agree. That oil is dirty, but auto trans fluid is rarely clean, and I don't think it's anything to worry about, so long as there aren't any small metal bits in the trans sump.

Nick

for those late 722.6 trannies without the tc drain plug they can be flushed through the cooler line.

see here:

http://www.benzworld.org/forums/w210...my-tranny.html

Before this devolves into a flush vs pan drop argument, I'm going to go the safe route and do another drain/fill, I'd rather not roll the dice with a flush. As others mentioned, I checked for a TCC plug, our version of the 722.6 doesn't have one.