Gear box fluid change?

[Bobby Dazzler]

It resets the driving style adaptations. Meaning - how high/low in the RPM range it shifts, also how long it holds gears before shifting to the next. The benefit is that if you drive granny style, you get good fuel economy, but if you decide to go all Fittipaldi - it will respond.

Popular gossip is that it monitors your behaviour over the last 40 shifts and adjust to that.

If you don't have a tremor in your foot, let it handle its own business.

It's often described as a reset, but I believe it simply fools the car into thinking you're driving like a loon, because the driver's foot has been pinned to the floor for ten seconds from a dead start, and sharpens it's reactions accordingly.

The gearbox will slow down it's reactions again if you don't then drive like a loon when the engine is running.

You can achieve the same result as the "reset" by finding an empty dual carriageway and gun it from rest.

 

[tanuie]

Hi I am near Colchester is the cowdray a Mercedes garage? And could I ask you what it cost please thanks

Had mine done with brake fluid change and new wiper blades at my local indy and the cost was £280, i think the 7g gearbox is a bit more expensive than the five speed.
Hope this helps.

 

[zipdip]

Hi I am near Colchester is the cowdray a Mercedes garage? And could I ask you what it cost please thanks

Deane you have not been paying attention,as you live around the corner from me you should know that CCC is the place to use for your Mercedes work,they are very reasonable ,they do not have pristine workshops,they can offer you a car while yours is worked on I always refuse as I just spend the day in Colchester or visit friends,the cars are a focus or a renault both quiet old,my car is due a service and I might have the gearbox oil changed again,you ask is it a Mercedes garage well not exclusive they work on lots of top makes,they are genuine guys who do not go for the throat with the bill.

 

[Gary129]

Done mine and its a lot smother change.

 

[ToeKnee]

No that will only get you about 3 of the almost 8l out of the system... Needs to be flushed too

I'm not too far from Nuneaton, what is the approximate charge for a 722.9 gearbox fluid change/flush and filter change please?

 

[Beaky59]

Absolutely. Get the fluid changed

Do you flush all the oil out, I believe Star Autos Services in Huntington use some machine to suck all the oil out?

 

[DSM10000]

Do you flush all the oil out, I believe Star Autos Services in Huntington use some machine to suck all the oil out?

You can only drain the sump by this method not the fluid in the Torque converter, cooler and pipework.

 

[Beaky59]

You can only drain the sump by this method not the fluid in the Torque converter, cooler and pipework.

I assume most competent Indie's know the correct technique for getting most if not all od the oil out.

 

[DSM10000]

I assume most competent Indie's know the correct technique for getting most if not all od the oil out.

Then you assume incorrectly.

How do you remove oil from the T/C etc by simply siphoning the old oil from the sump? you have to drop the sump to clean it, check for debris and change the filter.

 

[pmcgsmurf]

There is an official MB procedure for draining the TC (with no drain plug).

You do the ATF change via the sump as normal fitting a new filter etc. refilling around 5 litres.
Then you disconnect the ATF line to the cooler, start the car, drain 3l stop, refill 3l and do this 3 times.
I have the document somewhere that describes this and did this last time I changed the ATF on the W211, fluid coming out goes from dirty black to clean red.

 

[E55BOF]

I knew that on the 7G box the torque converter fluid could only be replaced by pumping it out with the transmission running, but I've never heard that it had to be done three times; that would mean throwing away six litres of fluid as well as what was in the box originally. I've just had the 7G in the ML serviced at Wayne Gates, and the charge for new fluid certainly wasn't enough to cover an extra six litres.

 

[Beaky59]

I knew that on the 7G box the torque converter fluid could only be replaced by pumping it out with the transmission running, but I've never heard that it had to be done three times; that would mean throwing away six litres of fluid as well as what was in the box originally. I've just had the 7G in the ML serviced at Wayne Gates, and the charge for new fluid certainly wasn't enough to cover an extra six litres.

Ditto, Wayne did mine last Friday

 

[pmcgsmurf]

I knew that on the 7G box the torque converter fluid could only be replaced by pumping it out with the transmission running, but I've never heard that it had to be done three times; that would mean throwing away six litres of fluid as well as what was in the box originally. I've just had the 7G in the ML serviced at Wayne Gates, and the charge for new fluid certainly wasn't enough to cover an extra six litres.

Details attached here, says 14L required for the flush.

There must be some garages that use a flush machine to do this too.

 

[DSM10000]

I knew that on the 7G box the torque converter fluid could only be replaced by pumping it out with the transmission running, but I've never heard that it had to be done three times; that would mean throwing away six litres of fluid as well as what was in the box originally. I've just had the 7G in the ML serviced at Wayne Gates, and the charge for new fluid certainly wasn't enough to cover an extra six litres.

Nor when I had mine changed at PCS

 

[markjay]

When MB Brooklands did the ATF on my 7g+ box last year, they said the TC had a drain plug and they drained it. There was no mentioning of any additional flush or the oil cooler.