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Picked up a 2006 C55 and need to address the noisy transmission pump. It’s definitely the trans pump, it’s really loud and whiny but the converter. I assume that all the 722.6 pumps are the same, but I could be mistaken.
I was considering a refurbished pump as it seems a new one is in the $800 area. I was going to replace the bushing and seal while I was in there, the trans shifts fine and doesn’t flare up. Anything else while I am in there?
Is there a better new alternative? Thanks
Pull the pump off first and dissasemble it to make sure its eating itself before you spend money. The gears will be gouging out the housing if it's going bad and this will normally happen when the pump bushing becomes worn out and the gears get "pushed" to one side.
Converter and pump noises are very close to the same so be carefull.
To test put the car in gear and see if the pitch changes.
Than give a little throttle to put a load on it. Now if the sound changes its more than likely the converter because that is what is taking the load, the pump is just in a constant state of pressure so the noise with that will always be the same.
This is not 100% fact every time so be carefull. OR.....just change the pump and converter and call it a day.
Thank you, I bought the car and believe that the PO changed the conductor plate. The fluid looks new, but when I drained the pan I got 1.5 quarts out. I know from all my other 722.6 that’s not nearly enough. The PO thought the noise was timing chain and went as far as taking the valve covers off to inspect, and then condemning it as engine noise.
When the car is running it certainly sounds like the oil pump or timing chain, but on the lift the noise is definitely coming from the converter area. He said it started when he floored it to pass a car, so I would guess that after he only put 1.5 quarts of fluid back in , the pump didn’t enjoy that. In gear or out of gear it makes no difference in sound, but definitely quieter with 3.75 quarts instead or the 1.5 that it had.
Not too much metal in the pan, but some ferrous and some aluminum, I would guess from the pump. Trans shifts fine and there is no harsh engagement, and no apparent slip or flare. On the hunt for a pump that doesn’t break the bank, but lasts
I just ordered one, they seem to be the same regardless of amg or not. Relatively simple to replace comes with seals and bushing. That’s the car, the eventual plan is to put the extra m113k dropout with trans in there this winter, but for now a trans pump will make it work.
02-26-2023, 07:49 PM
