xsever

Hello everyone,

My German-spec 2005 CLK 320 started making an intermittent noise/vibration while driving (uphill or flat not in downhill) last Friday. It's a noise/vibration associated with something turning and I believe it's the transmission or transmission shaft. No errors appeared with a generic OBDII scanners (4 scans since Friday).

Luckily I have a friend who is an MB Technician working for the local MB dealership so him and I took it for a drive and he got to experience the noise and vibration.

We replaced the transmission mount at his own shop yesterday and the problem is still there. We noticed the transmission mount bracket not to be very level which obviously is causing the transmission not be level so we may be replacing that next.

Other findings of the inspection was that the transmission shaft central bearing needs replacement since it's wearing out and the shaft is resting too low inside the bearing. Could these cause such noise/vibration?

I basically want to know what's everyone's opinion on this as we go through diagnosing the problem. I did some research before posting and there are a lot of options.

Thank you,

mrbobby

The drive line angles are very sensitive and indeed could cause the vibration. I suspect that if you replace the necessary components to realign the drive shaft you will find the problem cured.

Glyn M Ruck

Check front engine mountings as well. Check transmission output flange nut is tight. Check flex discs for cracks & centre propshaft bearing.

xsever

My friend and I worked on the car yesterday.

Here's what we did:

We replaced the transmission mount bracket since the existing one was very bent. The part, if pressed on on one side would oscillate back and from from how uneven it was. With the new one, the transmission is perfectly level. We also replaced the catalytic converter bracket which is right by the transmission mount bracket. This one was bent a bit too.

We dropped the pan and changed ATF+filter+gasket and we also changed the pilot bushing connector since we found a bit of oil.

We replaced the fuel filter (maintenance item due at 100K Km).

We test drove the car and the vibration is gone and the shifts are much smoother. I then took a 60 km drive with highway and uphill driving and all is well.

Glyn M Ruck

Great! That rear mounting often causes problems. Check you front mounting as well. If they are bad/worn they will damage the rear mounting again.

xsever

The vibration came back earlier this week yet not as strong.

We decided to drop the pan and to our surprise found water traces in it. I stopped driving the car immediately and knew that the radiator is bad.

What shocked me is that my car is an MY2005 so I was under the impression that there is no way it has the Valeo radiator rather than the updated Behr one. Well, to my surprise we found out it had a Valeo!!!!! I should have been more precise when I first bought the car since I know about the Valeo mess.

Anyway, I bought a new Behr radiator and installed it and did a full ATF flush with 14 litres.

Everything is smooth now and no more vibrations but on the 80km test drive I did, I noticed a bit of hesitation (if I may) going uphill at 90-95 Km/h. Driving uphill today was perfectly fine with no hesitation.

My MB Tech friend believes it's the torque converter and he advised me to keep driving it a bit to give the ATF a chance to lubricate everything. We are going to continue to monitor and hopefully by changing the radiator this early, we were able to save the transmission and the torque converter.

What does everyone think?

Rudeney

Coolant in the transmission fluid rarely damages anything. Yours will probably be fine. If you are concerned, do another full flush and filter change after few thousand kms.

gaazmon

VALEO in an 05??? somebody at MB must've really gone digging through the parts bin that day

Rudeney

I thought they stopped using the Valeo in the early MY2004 build (so very late calendar year 2003). Is it possible this car is a MY2004 that is a "2005 plate"? Model year can become confusing in parts of the world where they use the registration year instead of production run to date a car.

xsever

Thanks for all your input guys. Here is my VIN: WDB2093651F136567

gaazmon

i had an 02/04 built e320 that had valeo radiator

Rudeney

The delivery date on this car is 08/18/2004. It's possible that it is a very early MY2005, but with such an early delivery date, I would guess it isn't. Is it a "facelift" model? The easiest way to tell is if the radio and upper dash buttons are square or rounded - square is facelift. My guess is this is probably an early calendar year 2004 build that wasn't registered until August 2004, and that's how it ended up with a Valeo.

swatty

The vibration comes from a damaged convertor lockup clutch. I would replace the radiator and do a transmission oil flush. Twice would be good. If the problem persists you will need to remove the transmission and have the convertor serviced.

Edit, sorry just read your 2nd post, hope all goes well

xsever

The following were found on the Valeo radiator: Valeo A 203 500 10 03 10/04/03 27 014.

I am starting to wonder if the radiator has been changed from the factory installed one which should have been a BEHR because there's a big time gap between 2004/03 and 08/2004.

The buttons are square and I have the newer Command in the car so that's why I was sure it's 2005. I owned a 2003 previously and know what you're talking about in terms of these buttons. Mind you my car is German spec and not US.

optimusprime m1

So end game is that the transmission oil is cooled by the Radiator .And not through any other cooler .

Rudeney

Correct. The radiator has a separate chamber to coll the transmission fluid. The original Valeo radiators have a rubber seal on the transmission fluid inlet where it passes through the coolant chamber. It deteriorates and allows the mixing.

optimusprime m1

Thought so Rudeny . Much the same as the old oil coolers included inside the radiators. I dont think there is another way , that oil can gets inside the overflow bottle .Oter than head gasket failure ,do you ?

Rudeney

If it's transmission oil in the coolant, then it would be coming through the radiator. If it's engine oil in the coolant, it could be a head gasket issue, but it could also be the oil cooler or its gasket.