Wodeshed

Hi, guys-

I'm gathering up the stuff to do a transmission flush. I've got the pan gasket, filter, 14 qts of Shell ATF 134, pan bolts, drain plug replacement, crush washer in two sizes, and a electrical harness plug replacement.

My car is a 2005 CLK 320 with 140k miles, no transmission symptoms, and no prior fluid changes. I KNOW I've neglected maintenance, but I'm out to make amends.

I've been through all the transmission threads both here and at the other site, and I'm confused on two fronts. First, I'm not getting which line to undo on the radiator. If I understand it properly, the banjo bolt is on the passenger's side (right) and is probably overkill. I'm interested in the easier way. Can I just undo a transmission line to the radiator on the driver's side, connect via a tube and clamp to drain into a marked container?

Second question is about which line to use to refill fluid. I have TWO possible lines on this car. One is marked MB use only, with a black tab, and the other is a long line with an orange cap. I'll attach a photo I took while doing my EGR line. It looks for all the world like I have a line to insert an engine oil dipstick (orange capped line), and transmission fluid should go into the MB only black-capped tube. Can anyone confirm/correct me on that? It would be just my luck to pour transmission fluid into the oil pan and kill the car.

Oh, and one more thing, I've been through the w209 WIKI multiple times on this question, and have found no definitive answers to these two questions. It's especially confusing on the 722.6 transmission bulletin that it shows a hand pump but never discusses when to use it. My suspicion is that it's meant for refilling the torque converter, but mine has no drain plug.

Thanks in advance for your answers to these questions!

Quadcammer

the line to the oil cooler should be on the passenger side (if left hand drive).

The transmission fill tube will have a locking tab inside the black cap. You have to pry off the tab, push down the remainder, and then take the cap off.

The red is your dipstick tube.

Wodeshed

Sweet! So I can put a regular dipstick in the longer line instead of using the COMAND system to check oil level?

Wodeshed

So the remaining issue is which line to disconnect from the radiator. From the Mercedes EPC online I see the attached diagram, suggesting that the right (driver's) side line to the radiator (#10) is from the torque converter, and the left side (#60) goes back to the transmission. I'm thinking this will be the easier one to disconnect and connect to a length of 1.5" tube with a clamp. Can anyone confirm?

I'm really trying to avoid this jam nut/banjo bolt business.

Rudeney

Here are the WIS docs for doing a full flush:

http://benzbits.com/722_6/TransmissionFlush.pdf

The cooling line to remove is on the right (USA passenger) side. Note that the TRANSMISSION fluid level can only be checked by the optional dipstick - it's ENGINE OIL level that is checked on the MFD.

And don't confuse the engine oil dip tube with the transmission fluid dip tube. The engine oil dip tube is visible without removing the engine cover and should have a small, easily removable dust lug in it. The transmission dip tube can't be accessed until you remove the engine cover. The doc I linked above will show you the way to remove the locking cover on it.

Wodeshed

Thanks, Rodney.

I've read that WIS on the transmission flush, but it seemed like the banjo bolt removal was controversial. Some of the other posts on the subect talked about using the radiator incoming side of the transmission fluid line to drain because it's easier, but I couldn't tell where it disconnected. That's why I was asking. I know there will be residual fluid in the radiator, but that seemed like a small price to pay for an easier service.

As to the dipstick, I figured that the taller tube with the orange lug must have been for engine oil, but I wanted to be certain rather than risk putting transmission oil in the motor oil pan (as someone else recently did). What I wonder, though, is what is the purpose of that engine oil tube? It's not for adding oil, and lacking a dipstick it's not for checking oil, so I can't for the life of me figure out what it's supposed to be for. It's very un-German. I blame the Osti influencce.

By the way, I do have the transmission dipstick and infrared thermometer to check transmission oil temperature. What I wonder is whether I can get an engine oil dipstick to replace the orange lug and check motor oil in the conventional way?

So I guess those are my two questions:

Where to disconnect the oil line to the radiator on the driver's side (since I worry about removing some engine oil line or something), and

Can I get a conventional motor oil dipstick to replace the oil tube lug?

Wodeshed

Damn...one more question...

If you look at the WIS document you attached, which is identical to what's in the WIKI, it shows a pump at the bottom of the final page, but NOWHERE in the instructions do I see where to use it. I have one, but I wonder if the pump would only be used for refilling a torque converter? Mine isn't drainable, so I suppose the pump is superfluous. No pun intended.

Quadcammer

alright dude, i think you are confusing yourself.

This is very simple.

On the passenger side of your radiator (below the intake tube), you should notice a 5/8" fitting. No banjo or washers, just a nut.

steps:

1. drain tranny oil pan
2. remove bolts on oil pan
3. replace filter, clean pan, reinstall pan
4. take off the tranny fill line cap and put the same amount of fluid in as you took out.
5. remove the line from the radiator and attach a clear vinyl line to it. secure with hose clamp and run into a container in which you can see the fluid level.
6. start car very briefly untill you get about 2 quarts into your container.
7. Add 2 quarts new fluid
8. Repeat until the fluid coming out looks like the fluid going in.

Now, reinstall the tranny fluid line and go through the level check. Correct the fluid level and go for a drive and check several times. before putting a new locking tab in (not necessary but I do it).


Now as to the engine oil dipstick. I believe you can order one from mercedes but I don't know the part number.

Wodeshed

It's this thread that has me messed up, I guess. The original post befuddles me, and maybe makes me overthink it: http://tinyurl.com/nvarjtr

Wodeshed

This one at the OTHER forum puzzles me too. People talking about banjo bolts and needing some 14mm nut: http://tinyurl.com/o46gkfh

Rudeney

Regarding the engine oil dip tube, you can get a dipstick for manually checking the level. However, it is not meant to be left in place during vehicle operation.

Wodeshed

Here's a pic of what my radiator looks like. I take it that the incoming (hot) transmission fluid line connects on the upper right.

Kustom1911

Nice Radiator Pic.

Yes the upper right hose is the one to use to flush the transmission.

your pic shows the retaining clip to remove the hose, be careful not to remove it to far, as it can go flying across the shop. you will have to loosen the cooler line bracket to get enough play to remove the upper cooler line to put the drain hose on it.

I use a graduated drain jug that I made to measure the expelled Trans fluid, so I can add the exact amount. about 1-1/2 to 2 qts at a time. It takes between 12 - 14 qts for a pan drop, filter change, and flush.

I always replace the o-ring on the cooler line every time. the MB part #
028-977-62-48.

Wodeshed

Thanks!

Everybody was talking about bolts, so when I saw these clips I didn't know for sure that they were the transmission lines. Found this radiator photo on some replacement radiator website, and it's an exact match for mine.

I appreciate the tips!

Hsg08

To stop the confusion, all you guys have to do is buy the transmission sevice kit (this includes all the fluid and parts etc. that you need for the tranny service) from ECS Tuning and take your car to your trusted indy mechanic. Problem solve

tw2

Or you can do regular drain and fills like I decided to do (with a filter replacement every 2nd or 3rd time). No it is not as good as a full flush.

But if your fluid is not too bad to start with and you do it more frequently than 39,000 miles then it is a very simple DIY and will be just as effective in the long run. No messing around with fittings, hoses, machines etc. If you measure exactly how much you drain then you don't even need trial and error the level afterwards with the dipstick.

Wodeshed

I'm at 140k miles with a five speed transmission, so the full Monty is essential. And I'm committed to doing it myself. I've already got the parts, thanks.

Wodeshed

Thanks for the advice guys. I've just completed the transmission draining/pan cleaning/filter change and pan reinstall. I also replaced the electrical connector bushing, which WAS the old style, and there WAS oil inside the bushing. I've got that upper line to the radiator disconnected and attached to a 10' length of clear tubing, so I'm ready to flush in the morning.

I'm really glad to have done this job, especially because there was so much grit in the transmission pan. I haven't noticed it being hard shifting, but I can't imagine that symptom was far off.

One weird thing was that I only got about 3 liters of fluid out of the transmission pan. Maybe it was low from the bushing leak. Anyway, I do have the dipstick and infrared thermometer, plus a full case of Shell ATF 134 ready to roll, so I ought to be good now.

Thanks again.

tw2

You should only get about 3-3.5L from the pan. More if you manage to catch the fluid from the filter (mine missed the container).

xsever

When I did this on my 2005 CLK 320, I let the valve body drain for hours and I also replaced and captured the oil that was in the filter. The total was 4.4 litres.

If you let it drip for quite some time, you'd be surprised how much fluid that amounts to be.

Wodeshed

I don't doubt that that's true, given how I caught a fair amount of drips on my face while putting the pan back on!