2004 E320 CDi - Sluggish Gear Changes When Cold

[Razoo]

5-Speed 722.6 Gearbox

I have noticed that when driving off from a cold start (especially with the recent low temperatures), the transmission in first and second seems rather sluggish and slow to pick up.

Whilst the car will creep slowly forward on tickover, the engine revs seem to have to rise quite high before the transmission fully engages and any real progress is made.

This is particularly noticeable when I leave work where I have to negotiate a series of chicanes and speed humps at the Main Gate. These obstacles require gentle on/off throttle action that seems to confuse the transmission.

As I clear the Main Gate and press the throttle to accelerate away, the engine revs often rise to 1,800-2,000rpm, but the car doesn't seem to be in any gear. After a short delay, the transmision gets it act together and the car accelerates as expected. These problems do not occur when the engine and transmission are up to operating temperature.

Maybe this sluggish behaviour is normal modus operandi for a cold diesel automatic, I don't know - but it is in stark contrast to my 3.0 litre Vauxhall Senator, and my wife's 2.2 litre Vauxhall Zafira automatic, both of which drive perfectly from cold. In fact, the Zafira has one of the best auto-boxes I have ever driven.

The transmission oil and filter were changed in July 2008, but I don't believe the system was flushed and only the oil drained from the sump was renewed (i.e. only a 5 litre/60% capacity oil-change was carried out). The oil in the transmission is currently straw/brown, rather than red.

Now sometimes a MB Main Dealer deserves an accolade:

I telephoned Mercedes Benz of Newbury who offered to check the car out for me and ensure it was running the latest ECU software (it was). They gave the transmission a thorough check (including a road test), checked the oil level (it was OK), performed a glycol test (negative, although unfortunately I do have a Valeo radiator), confirmed that gear changes were being made at the correct speeds (they were) and couldn't find anything obviously wrong. They must have spent a couple of hours or so checking the car over, but they did not charge me.

It seems the next logical step would be another oil and filter change, but this time with a full flush to ensure that all of the transmission oil is replaced.

What does the team think?

Thanks,

Razoo

 

[whitenemesis]

I had something very similar. With me though it ws because a glow plug had failed (Glow plug light came back on after starting).

Changes were slow and slurred, first came in with a jolt..

Had the plug replaced and Wow! what a difference in the changes. I would expect the engine to run rough with a plug failure but the gearbox?

Still all a sorted now

 

[television]

The fluid goes brown the second you put it in, so that normal, I would wait till the weather picks up a little, the box will hold onto the lower gear when cold to warm up the CAT, dont somehow think that changing the fluid again will help

As whitenemisis if the engine power is down the box will be confused

 

[MB TECH WARRINGTON]

5-Speed 722.6 Gearbox

I have noticed that when driving off from a cold start (especially with the recent low temperatures), the transmission in first and second seems rather sluggish and slow to pick up.

Whilst the car will creep slowly forward on tickover, the engine revs seem to have to rise quite high before the transmission fully engages and any real progress is made.

This is particularly noticeable when I leave work where I have to negotiate a series of chicanes and speed humps at the Main Gate. These obstacles require gentle on/off throttle action that seems to confuse the transmission.

As I clear the Main Gate and press the throttle to accelerate away, the engine revs often rise to 1,800-2,000rpm, but the car doesn't seem to be in any gear. After a short delay, the transmision gets it act together and the car accelerates as expected. These problems do not occur when the engine and transmission are up to operating temperature.

Maybe this sluggish behaviour is normal modus operandi for a cold diesel automatic, I don't know - but it is in stark contrast to my 3.0 litre Vauxhall Senator, and my wife's 2.2 litre Vauxhall Zafira automatic, both of which drive perfectly from cold. In fact, the Zafira has one of the best auto-boxes I have ever driven.

The transmission oil and filter were changed in July 2008, but I don't believe the system was flushed and only the oil drained from the sump was renewed (i.e. only a 5 litre/60% capacity oil-change was carried out). The oil in the transmission is currently straw/brown, rather than red.

Now sometimes a MB Main Dealer deserves an accolade:

I telephoned Mercedes Benz of Newbury who offered to check the car out for me and ensure it was running the latest ECU software (it was). They gave the transmission a thorough check (including a road test), checked the oil level (it was OK), performed a glycol test (negative, although unfortunately I do have a Valeo radiator), confirmed that gear changes were being made at the correct speeds (they were) and couldn't find anything obviously wrong. They must have spent a couple of hours or so checking the car over, but they did not charge me.

It seems the next logical step would be another oil and filter change, but this time with a full flush to ensure that all of the transmission oil is replaced.

What does the team think?

Thanks,

Razoo

which gearbox mode are you in, c or s
if in c try it next time in s

but with any gearbox concerns get your level checked

 

[Razoo]

which gearbox mode are you in, c or s if in c try it next time in s

I run with the gearbox in mode 'S'. I could try it in mode 'C' to see if there's any change (no pun!).

but with any gearbox concerns get your level checked

A transmission oil level check was the first thing I did. I even treated myself to a MB transmission service dipstick. The level was OK.

When I experience the sluggish gearbox problem following a cold start, the impression I get is that the gearbox is lost somewhere between first and second gear.

I don't appear to have any glow plug problems and the engine starts very well. The engine does produce a loud, metallic tapping noise (like a noisy tappet) that varies with engine speed, until it warms up. The MB dealer said this was nothing to worry about, although I don't like it. Guess I'm too used to petrol engines.

Razoo

 

[Mercedes 190E]

Our 2004 320 CDi is exactly the same. I suspect it might just be a feature of the gearbox when cold.

 

[Razoo]

Our 2004 320 CDi is exactly the same. I suspect it might just be a feature of the gearbox when cold.

Thanks John, it's good to know I'm not alone!

This means that either I don't have a transmission problem, or we both do

One possible cause of the sluggish transmission when cold suggested to me is slow pick-up of the cold oil, maybe indicating a partially blocked strainer/filter. This is why I am tempted to do another oil and filter change myself, just to be sure everything is as it should be.

Regards,

Mike

 

[Autofix]

It is always difficult to judge something like this just by reading the symptoms but it sounds to me like it is normal. The best way to be sure would be to leave it in with your garage overnight so they can check it cold.

 

[Razoo]

It is always difficult to judge something like this just by reading the symptoms but it sounds to me like it is normal. The best way to be sure would be to leave it in with your garage overnight so they can check it cold.

Actually, MB of Newbury did keep the vehicle overnight to do a cold start the next day. They didn't find anything obviously wrong with the gearbox and suggested a transmission oil and filter change should be the next course of action.

I can live with this gearbox's sluggish pick-up from cold, if it's normal. Mind you, I don't see why it should be like this. Is the gearbox trying to be too clever? Maybe MB should enlist the services of a Vauxhall gearbox designer because if my E320 gearbox matched my wife's Zafira 2.2 automatic gearbox for smoothness and pick-up, I would be well pleased.

Razoo

 

[Parrot of Doom]

Maybe it isn't starting in first gear when cold.

 

[Razoo]

Maybe it isn't starting in first gear when cold.

Hi PoD,

I'm sure the gearbox is using first (based on the high revs/low mph). Maybe the issue is simply that the transmsission ECU holds first gear for so much longer from cold, resulting in lots of revs and little progress, until second gear is (eventually) selected.

Can anyone tell me the mph/1000 rpm for first and second gear, then I can check it out?

The Transmission No. is : 722626 05 376039

Thanks,

Razoo

 

[Rory]

performed a glycol test (negative, although unfortunately I do have a Valeo radiator),

If you're thinking of keeping the car for a while then you might want to think about having a pre-emptive radiator change (or have a separate oil coller fitted) at the same time as the ATF is changed. If nothing else, it will be a weight off your mind.

 

[Razoo]

If you're thinking of keeping the car for a while then you might want to think about having a pre-emptive radiator change (or have a separate oil cooler fitted) at the same time as the ATF is changed. If nothing else, it will be a weight off your mind.

I certainly wasn't pleased to be told my E320 CDi had a Valeo radiator fitted, especially as I was told it had a Behr radiator when I was buying the vehicle

However, my MB Main Dealer assures me that although it is the notorious Valeo, it is a modified version (introduced September 2003?) to address the well-documented problem of the integral transmission oil cooler failing and allowing coolant to enter the transmission, causing glycol contamination of the ATF with disastrous (and expensive) consequences.

Can anyone confirm whether a modified Valeo radiator was in fact introduced in late 2003, before the changeover to the Behr radiator? My E320 was built in June 2004.

Thanks,

Razoo

 

[wportre]

It was. The "dud" and replacement Valeo radiators have visible differences in the end-cap welding. A forum search will reveal photos. If you cannot find them, ask and I or someone can dig them out.

 

[television]

The modified rad has a white circular label stuck onto the oil cooler

 

[Razoo]

It was. The "dud" and replacement Valeo radiators have visible differences in the end-cap welding. A forum search will reveal photos. If you cannot find them, ask and I or someone can dig them out.

I have downloaded and printed several pictures of Valeo and Behr radiators, but the detail/resolution was not good enough for me to ID my rad.

If you can post or send me some good pictures of the various radiators, I would be very grateful. I'd like to see for myself that I have the updated radiator.

Thanks,

Razoo

 

[Razoo]

The modified rad has a white circular label stuck onto the oil cooler

I haven't sussed all the radiators fitted to my E320 CDi yet. There appears to be the radiator/transmission oil cooler and the aircon heat exchanger fitted one behind the other. Then, in front, there's the smaller, silver coloured radiator tucked down low behind the front bumper. I assume that's the oil cooler. My oil cooler is a Behr. I'll check for a circular, white label this weekend.

Would MB normally fit a Valeo rad and a Behr oil-cooler?

Just above the oil-cooler is a black, folded, tubular steel cooling loop. I haven't traced its pipes yet. Is this a cooler for the power steering?

Thanks,

Razoo

 

[delboy777]

Is this Valeo radiator something i should be worried about ?? Better still is there anything i can do to prevent a failure

 

[wportre]

MAB01UK's done the hard work on Valeo http://forums.mercedesclub.org.uk/showthread.php?p=231842 . Razzo, not certain but probably: black simple loop = oil cooler. Silver, low = aircon. AT cooled by heat exchanger in the main rad. (Look for pipes entering and running aft: drop the screening panel behind the bumper if you have one: if you do (4 self-tapping nuts) it becomes clear as day.

 

[wportre]

delboy777 possibly: check the pics. Personally, if my rad was one of the suspect ones, I'd have it out of there (as per MAB01UK's link, an easy DIY) before driving another foot.

From Merc:

"Topic number
GI27.55-P-012236
Version
6
Construction Group
27.55 Transmission oil cooling
Date
01-07-2005
Validity
Model series 203 up to production date 9/2003 with M111/271/112/OM646/OM611/612.990 and automatic transmission 722.6
Model series 209 up to production date 9/2003 with M271/112/113/OM612 and automatic transmission 722.6
Model series 211 up to production date 9/2003 with M271/113/OM628/647/648 and automatic transmission 722.6
Change Reason
Addition of damage code list to be used in case of repair
Damage Code
2743104

Complaint During gentle acceleration humming/droning noises can occur in the speed range between 1200 - 2500 rpm. Likewise it cannot be ruled out that the vehicle will jolt in the rpm range stated.

The complaint can be reproduced at any time.

Cause The complaint can be caused by a faulty transmission control unit, a torque converter lockup clutch which has not been adapted, a fouled torque converter lockup clutch disk or by glycol in the transmission oil, see Tips documents.

"