mis3

Prompted by the other thread on warning on changing ATF of 722.9 transmission, I have questions for my 722.6.

The ATF of 2004 CLK320 is supposed to last lifetime and against my SA advice, I asked the dealership to change the ATF on Feb-2009. At that time, they did use the correct ATF for my transmission.

Now that I drove this car for another 3 years (maybe 80k km), I would like to change the ATF again. I went to the dealership but they no longer stocked the specific ATF for 722.6. They said the ATF for 722.6 and 722.9 were inter-changable.

According to this forum. I should not use the ATF of 722.9 on a 722.6. I should only use ATF with part no 001-989-21-03-10. What should I do? Should I go ahead to let them change the ATF?

M-bENZ

This is a good info. i would like to know too hmm..

Glyn M Ruck

Mercedes now mandate that you only use the 722.9 - 236.14 fluid on 722.6 transmissions. It is the best for both transmission types. The 722.6 transmission has always required servicing every 39K miles or 60K Km's in ROW. It's never been filled for life. Filled for life = short life. So please ignore that BS.

grane

Glyn,

My question is similar to the OP who started the thread.

My MB tech had a large cache of the MB labeled 722.6 fluid. he bought this on purpose because the day job dealership was having "issues" with the transitional 7 spd fluid.

When I had my fluid changed 2 years ago he insisted on using this original .6 fluid on the 5 speed following the complete 1x litre procedure, rather than the "interim" multi trans fluid.

I trust him, since he is conscientious, so if he stocks the new fluid .14 I should use this if no longer has the old stock? What happens if he has both, and I have the 5 speed? Which is preferred?

If not MB branded . 14 fluids which brands do you like, and how does onerecognize them?

Btw if I put < 5k miles on the car per year what is the yearly interval for the .6 transmission fluid and filter change, as you might do to your ride?

mis3

I did some readings and more and more I believe that I should stick with the 722.6 fluid.
More so since I want to do only the partial flush. It is not a good idea to mix both fluids in the transmission. The dealership did it last time using 722.6 ATF with good results.

The question is since the dealerships no longer stock this fluid, where do I get it locally in Toronto?

Glyn M Ruck

To both of you. The 236.14 fluid is superior to the old fluid in ALL respects. I was involved in it's development for my company. Better anti oxidation due to far better synthetic base fluid, better viscosity maintenance, longer life in service, far longer maintenance of shift shock quality, lower wear rates. There is only one approved additive system so whether you buy Fuchs, Benz OE, Febi or Shell it makes no difference. Shell sells their fluid at the most reasonable price via Ryderfleetproducts in the US. The fluid is identified in all cases on the pack as approved against MB 236.14. Ignore any fluid that says "meets the requirements of"

Remember that the 722.9 is a development of the 722.6 with a Ravigneaux gearset to achieve the extra ratios.

There has never been a fluid issue in all the generational changes from 236.1 to 236.14. Early 722.9 transmissions had some TCU issues, speed sensor/conductor plate issues, fluid level issues hence the new spill tube height & pan redesign etc. None related to fluid. It has been a steady progression as Benz has strived for longer fluid life without transmission performance change.

The old & new fluids are designed to be miscible & fungible. However the new fluid uses better friction modifiers so to enjoy the full benefit a complete change is sensible.

There is a HUGE amount of crap spoken on the internet & forums about this issue from - changing your fluid could lead to transmission failure, leave the old fluid in it, to the old fluid is better than the new. What utter bollocks. Time & development moves on and the oil industry has better components available to it than when the earlier generation fluids were developed. What disgusts me is how often ignorant MB Techs that are nothing more than parts changers in many cases pass this misinformation around. Choose carefully who you listen to.

If you run low mileage as I tend to then change fluid every 5 years if you want to adopt a belt & bracers approach. I changed mine at 7 years on my last car & all was absolutely fine.

Please note that Benz changed the 722.6 recommendation in 2008. This is not new! The 722.6 transmission is still used in some diesel models although being phased out. It is filled with 236.14 fluid ex factory.


Approved fluids as of now.

Glyn M Ruck

Here:

Ryder fleet products have by far the best deal on this product by Shell at under US$ 6 per quart. Most dealers are charging over $20/quart. The Shell product is fully approved. Many use Fuchs Titan 4134 as well.

See description. It is Shell product in a Shell container - Pennzoil is owned by Shell. Many have confirmed correct product in Shell packaging on receipt.

http://www.ryderfleetproducts.com/ry...oductDetail.do

mis3

So, in your opinion, my 2004 CLK320, which has the 5-speed 722.6 transmission, can use the 236.14 fluid?

How about partial flush? This would mean that the 2 fluids will mix inside the transmission. Is this OK or should I look for the 236.10 fluid?

Glyn M Ruck

Yes with no problem at all. You have no TC drain so either do the half drain or a full flush - I can post methods if interested.

If you do the half drain, drain hot & leave it draining for as long as possible.

If the present fluid does not look good then do the full flush which takes 14 quarts otherwise you are just putting crap in the ice cream.

I could curse Benz for removing the TC drain plug in 1999. Thank god it's back.

mis3

Thanks, Ruck.

I won't be doing the flush myself. MB did it for me 3 years ago, it was a partial flush and it took 5 liters.

How can I tell if the old fluid is bad? Color?

Glyn M Ruck

If it is very black it's oxidised, If it smells burnt it's oxidised, If it has particulate contamination e.g. clutch pack material & other wear debris in it. The other issue can be coolant contamination from a leaking cooler but then it will look like crap.

If it is slightly darkened but clear & bright it is OK & normal.

On my C240 with a 722.6 we changed the fluid - half change method - at 7 years 60K Km's. The fluid that came out looked OK. Had I kept the car it was my plan to do another half change 30K Km's later.

mis3

Before I asked the last question, I thought I would check the ATF myself using a dipstick. Then I read on and found that my car did not come with a dipstick to check transmission fluid. I will have to rely on the MB tech who will do the partial flush.

On the different but related topic, how does one damage the transmission? I know that towing can cause stress or overheat for a transmission.

I do not haul anything with my car. is there any day-to-day driving habits that we should avoid to preserve the transmission?

Glyn M Ruck

Endless high torque gear changes at maximum throttle will always be hard on the transmission. Don't coast out of "Drive" - with the 722.6 at least the oil pump still runs but the practice is not recommended.

The 722.6 is an extremely robust transmission. The only failure mode seen from time to time is usually the first to second gear one way clutch at extremely high mileage in Taxi service from just too many high torque changes.

Properly serviced the 722.6 will do a million kilometres. I know of a number in Asia that have done just that & we have an E240 at the office in Cape Town that is heading for 700,000Km with no major repairs. Transmission is still fine. The car does taxi service to & from our airport.

So drive sensibly, service correctly & watch the electrohydraulic bushing where the TCU plugs into the front RHS diagonal of the transmission for leaks & all will be well. O rings sometimes fail on that plug bushing. $8 replacement part so no big deal.

mis3

What did you mean "Don't coast out of drive"? Did you mean not to put the gear in Neutral; like when approaching a red light?

I understand that at any gear, I can shift to neutral. On the other hnad, it is risky to shift to gear when driving in neutral.

Glyn M Ruck

Yes - never shift in to neutral while the car is moving. Be it approaching a traffic light or when running down hill on the open road. A practice I believe the Americans call "hypermiling".

mis3

I know that shifting to neutral while driving is not a good practise. This is dangeous because we cannot control the speed while in neutral.

I did not know that this will hurt the transmission !!!

Glyn M Ruck

From the Owner's Manual. Basically if the transmission is in Neutral none of the protection systems work. e.g. If the torque converter is overheating the TCU will sense this & release the TC lockup clutch while at the same time allowing greater fluid flow to the converter & via the transmission cooler while in Drive. This will not happen in Neutral as an example.



The safety issues are obvious.

jbenz99

I used Valvoline MaxLife transmission fluid on my w208 430 and drove over 30,000 miles with no problems when I used to own it. I just recently used it on my new W209 500 and its shifts smoothly and it cost only about $3.65 a Qt .

Valvoline Link:http://www.valvoline.com/pdf/maxlife_atf.pdf

Glyn M Ruck

Please people. On no account use non approved fluids in these transmissions. One size fit's all does not work in modern transmissions. The Frictional properties of the Valvoline fluid are wrong just as a start.

Benz spends a fortune on it's approval process to protect it's product & it's customers. The oil industry likewise spends a lot of money meeting Benz specifications. There is a very good reason that so few fluids are approved.

There is also a good reason that the Benz fluid costs more. It uses better components in the blend. That does not mean that you have to pay $20+ per quart but Shell & Fuchs pricing is reasonable.

With a transmission rebuild costing upward of $8000 today to do it properly - do not mess with non approved fluids!

jbenz99

You and mercedes benz company may be correct on the subject But I talk out of experience using maxlife transmission fluid with no problems on my w208 and w209.I heard nothing of good reviews of other people using maxlife fluid on there benz vehicle's, plus there are a whole lot of indy shop using maxlife fluids on mb cars.But If you or anyone want to used oem fluids its great I never want to hate...lol

Glyn M Ruck

The principle of these forums is to give the best advice possible to owners. Your advice is not good & 30K miles is hardly a test of the effectiveness of the fluid. Somebody else will inherit your failure and any Indy using the wrong fluid is a clown & should not be working on Benz cars or any car for that matter. Ford & GM have their own unified spec these days & the Benz fluid is not suitable for them either. Honda have their own requirements & so on.

Benz & the oil industry spend a fortune on fluid development & some backyard grease monkey of an Indy knows better. I think not.

Peace!

jbenz99

I don't want to start something negatively with you over this tread I am not here for that ! All I am saying is I have used this fluid and many other MB forum member's and Mbenz owners and there are zero complitants about Valvoline maxlife transmission fluid check the reviews for yourself . I am just sharing my experiences and opinion just like you! I have use this fluid already on few cars with no issue what so ever. Again I am not saying to others " don't buy factory fluids " dont 't quote me in this matter .Plus I don't want to spent over $20 a Qt compare to $3 and some cents for maxlife...God bless !

mis3

I will do the partial flush and oil change in the dealership in Feb. They will use the new ATF so, I will mix the 2 fluids in the transmission. Hope all OK.

Glyn M Ruck

Lubrication is my job - see my profile. The use of a product like Valvoline Maxlife will have a detrimental influence on the transmission over time. I'm not stating an opinion. I've done the hard testing.

Seems you don't keep your cars very long but if you make a properly recorded 39K mile fluid change please send the used oil sample to Blackstone & post the analysis result. Then we can discuss clutch pack wear rates etc.

jbenz99

Valvoline has been developing high performance products and services for more than 140 years - longer than any other motor oil company.At there very low prices I will use it and recommended it to others .I am also a certified auto tech with over 25 years of experence working on all makes and model cars my shop uses max life and many other shop uses it too and I never heard any bad review over maxlife in my area I am not saying that oem fluids are bad all I am saying Its way over price !