Gearbox Oil - When to change?

[mpc]

What are the tell tale signs that gearbox oil needs replacing.
I have a 61 plate C250 S204 (67k on the clock) that I've had approx 3 months now. I sometimes find the gear changing a bit lumpy and not smooth like my friends E220.
I don't know the service history of my car (not available when I bought it).
Could it just be it needs the fluid changing?

 

[gianton]

What year is yours? Mine is an S204 C250 CDI 4Matic 2013 model with 7g+ gearbox and the oil/filter needs changing every 125k kms as per the manual. My car has 240k kms on the clock and had it done twice so far.


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[mpc]

mine is a 61 plate (September 2011)

 

[JohnBell]

What are the tell tale signs that gearbox oil needs replacing. I have a 61 plate C250 S204 (67k on the clock) that I've had approx 3 months now. I sometimes find the gear changing a bit lumpy and not smooth like my friends E220. I don't know the service history of my car (not available when I bought it). Could it just be it needs the fluid changing?

Yep i would have it renewed if there is no record of it being changed.

 

[flowrider]

I believe the recommendation is to change the ATF every 4 years.

 

[gianton]

mine is a 61 plate (September 2011)

Check with your local MB dealer what type of gearbox you have. If it's the 7g and not the 7g+ it needs changing every 60k kms. I have all this info from my MB dealer and the car's Maintenance Booklet.

Also it's best to have the TC oil changed too, on mine took 9,7 litres of oil.

 

[mpc]

whats tc oil?

 

[gianton]

whats tc oil?

Torque Convertor

 

[gianton]

I believe the recommendation is to change the ATF every 4 years.

Well my car did 240k kms in 4 years... I don't think that's the rule. MB Taxi drivers in Greece (with the 7g+ gearbox) change their car's oil/filter every 80k kms which they do that in less than 6 months.

 

[Smart320]

Rule is mileage or time whichever comes first. My 211 is 40k miles or 4 years. It will get changed next service T 4 years, will only have covered about 18 k miles

 

[Deleted member 6183]

It's unclear.

I phoned my dealer about the Mrs SLK who first said that it's at 4 years then 5 and also mentioned that it might not need doing at all.

Consensus is 5 years which would be next service although I suspect that this might be a sales pitch for a service plan.

 

[gianton]

It's unclear.

I phoned my dealer about the Mrs SLK who first said that it's at 4 years then 5 and also mentioned that it might not need doing at all.

Consensus is 5 years which would be next service although I suspect that this might be a sales pitch for a service plan.

My previous car was an Audi A6 Allroad 3.0 TDI with a 6 speed auto gearbox. Audi dealer said to me that the gearbox is "sealed for life" but when I contacted ZF by email recommended an oil/filter change every 80k kms.
Mercedes has in the maintenance plan to change the auto gearbox oil which is a good thing to do. Better to be safe than sorry with this stuff as they're very pricey to fix or change.
It's what Smart320 said the rule is either depended on time or mileage whichever comes first.

 

[Tuercas viejas]

There is a rule of thumb.
60,000 miles for light duty like a car.
40,000 miles for say a Sprinter doing heavy hauling or an RV /camper type conversion on a 3500 style chassis cab. .
With the average customer of mine doing about 10,000 mile a year that adds up to about four to six year service intervals.

Many MB 722 series transmissions have a torque converter drain plug that allows you to drop as much as you can from the unit as a whole .

For info on the internal conductor plate sit two encapsulated speed sensors.
They have two functions essentially picking up clutch pack drum speeds.
Dirt/contamination., fluid constituent separation etc coat the speed sensor faces and corrupt the speed signal giving erratic changes and ultimately driveability issues.

I recommend every 40,000 miles for that reason alone and it seems to be a point where enough contamination & heat related degradation of the fluid is starting to go really acidic from it normally alkaline state when new.
Leaving a change too long essentially shocks the transmission if it is made to go from a high acidic state to back to alkaline, which often strips off varnishes and "junk" in the box which can cause some serious issues.

In many cases I won't do a service on a high mileage transmission if it has not been changed in its lifetime or shows signs of abject neglect.

Tuercas Viejas

 

[clk320x]

There is a rule of thumb.
60,000 miles for light duty like a car.
40,000 miles for say a Sprinter doing heavy hauling or an RV /camper type conversion on a 3500 style chassis cab. .
With the average customer of mine doing about 10,000 mile a year that adds up to about four to six year service intervals.

Many MB 722 series transmissions have a torque converter drain plug that allows you to drop as much as you can from the unit as a whole .

For info on the internal conductor plate sit two encapsulated speed sensors.
They have two functions essentially picking up clutch pack drum speeds.
Dirt/contamination., fluid constituent separation etc coat the speed sensor faces and corrupt the speed signal giving erratic changes and ultimately driveability issues.

I recommend every 40,000 miles for that reason alone and it seems to be a point where enough contamination & heat related degradation of the fluid is starting to go really acidic from it normally alkaline state when new.
Leaving a change too long essentially shocks the transmission if it is made to go from a high acidic state to back to alkaline, which often strips off varnishes and "junk" in the box which can cause some serious issues.

In many cases I won't do a service on a high mileage transmission if it has not been changed in its lifetime or shows signs of abject neglect.

Tuercas Viejas

How about mine, it's a 5 speed CLK320 03..

Last changed at around 55-60k I think

Now on 112k...

Cheers

 

[gunning]

How about mine, it's a 5 speed CLK320 03.. Last changed at around 55-60k I think Now on 112k... Cheers

I don't like burning money but I'm having mine done on the CLS as it's simply worth doing for piece of mind.

I think an indi is charging me circa £120

 

[clk320x]

I don't like burning money but I'm having mine done on the CLS as it's simply worth doing for piece of mind.

I think an indi is charging me circa £120

When last changed? What miles?

Cheers

 

[mpc]

I've got mine booked in to get oil replaced for peace of mind.

 

[geraldrobins]

With the 7g plus its recommended at 5 years or 75000 miles and whichever is sooner.
Mine was changed at 5 years old and 52k. I think this is the general recommendation but best to check with MB

 

[AMGeed]

When last changed? What miles?

Cheers

Yours is a 5g and 37k mile intervals are recommended for ATF changes.

 

[clk320x]

Yours is a 5g and 37k mile intervals are recommended for ATF changes.

Oh really..

How much should it cost?