tw2

Just starting to think about some maintenance, my car has very low mileage (22,000 miles) but unknown service history. I have done a couple of transmission fluid changes (4.4 litres, not full flush) on my old CLK55 so I have the transmission dipstick, I also have a drain plug, crush washers, those red plastic locking clips etc. Gasket, electrohydraulic bush and filter I would need to order but they are cheap.

I used an infra red temperature gun on the transmission pan to previously measure the 80 C degree operating temperature. I couldn't get it that high by driving around but I found raising rpm to 1000 in drive with the foot on the brake heated up the fluid very quickly to 80 degrees to measure the level.

Is this ghetto? should I just get the dealer to do it? They would charge about 3x the cost of just the parts for me to do it but obviously they have STAR for adaptations etc and they quoted 8 litres which I assume would be a full flush. The CLK did need a transmission rebuild 18 months after my last fluid change but the friction plates were worn and K2 clutch was slipping, dealer even said the fluid level was perfect but it has me wondering if I should just leave it to them.

MACEDON

Drain the fluid, measure EXACTLY how much came out, put the plug back in, and put in exactly that much fluid back.

Very simple. Just make sure you use spec fluid.

If you do a filter swap, open the pan, let it drip as much as possible, measure exactly how much came out, put exactly that much in.

Even if you don't get the fluid level right you can drive around for 20 minutes, while car is runnning in P measure the fluid level and it should match the zone on your dipstick to make sure.

But for as long as you match what came out with what you put in you should be good (given the fluid level now is at a proper level). No need for the dealer.


In fact, if you buy a little hand pump for fluid and a long enough tube you can just suck fluid out from the top, measure how much came out and put that much fluid in.

A partial change is still better than no change. Idk how they're going to drain all 8 liters out honestly, typically shops around here charge for 4 quarts. Do a few partial changes yourself, one a year and you're fine.

BoostedAero

All you my friend, put the money in a roth ira and have a vacation to the bahamas in 20 years on me


https://fcpeuroblog.com/blog/mercede...transmissions/

Note. I start with 3.5qts and then add ***if needed*** to satisfy the 80* mark on my dip stick


Shell 134 is MB Spec and light on the wallet

MACEDON

This is as easy as an engine oil change really just get a measuring cup and measure out exactly how much came out. Usually 3.5qt like boosted said. It's a good idea to change out the filter it's very easy.

tw2

Ok, I will give it a go. I would like to replace the electrical bush sooner rather than later. I will try and drain the pan first, then put the drain plug back in. Then I guess let it drip for several hours into the mostly empty pan. Getting the fluid out of the filter to measure without it going everywhere was my main problem last time.

Dealer wants NZ$52 per litre for fluid. I might get an 8L fuch titan from ebay since their international shipping is very competitive compared to the online parts stores, I think it will come to around NZ$173 vs $416 (8L at dealer) and I should have more than enough for another change in the future.

How do you guys get it to 80 degrees? Last time I did some spirited driving and immediately jump out the car and use the temp gun and still max was around 65-70. Using the torque converter to heat it up was all I could do to reach 80.

Or do you just measure the fluid level at whatever warm temperature you happen to get at idle and then replicate that again after the refill?

bbirdwell

You can measure it at 25C. You can measure it at 80C. You can measure it at 50C (a bit more work but you can do it). Don't fixate on a couple of millimeters of oil level; you'll get stuck in "analysis paralysis". Macedon has it right; for the first pass measure and replace what came out. I would then recommend one verify with a dip stick (belt and suspenders approach) at cold and warm temps.

If you are only changing the fluid and electrical plug there is no adaptation involved; no need for DAS/STAR/Xentry. The diagnostic system is required for clearing hard codes due to electrical faults and comes in very handy for determining the mechanical wear on the transmission by reading out the "fill times" for the various gears. 0-15 will be the values read out; 0 cycles to pressurize the clutch pack means "new", 15 cycles to pressurize the clutch pack means "call a tow truck cause this car ain't going anywhere" (I jest but only a little).

Also, after replacing the fluid, prior to measuring level remember to hold the car in place with the brake (engine running) while you move the shift lever through the gears; reverse, drive, 1st, 2nd, etc. to ensure you refill all nooks and crannies. Measure the fluid level after you have done this. Edit: I see the link BoostedAero posted says to do exactly this. :-)

tw2

Thank you for the advice. I will do it myself again. Time to order some stuff and get grubby under the car.

tw2

Does anyone happen to know who the oem manufacturer is for the transmission pan gasket and filter? I usually choose these companies over "genuine" Mercedes if I can.

pumpedTSI

I would go OEM on things like tranny filters.....theyre cheap and you dont want issues....

tw2

I always go oem in one way or another. For example if my understanding is correct lemfoerder make the suspension parts for Mercedes. The only difference is the cost. Meyle etc also make them but they are not Mercedes supplier so I wouldn't choose them.

I will definitely go with Mercedes branded transmission parts if I can't find their supplier for cheaper.

FunkTron

https://fcpeuroblog.com/blog/posts/m...transmissions/

updated that link for ya

tw2

Just did fluid change today. Fluid came out of socket after removing the harness. I am pretty sure this means the pilot bushing was leaking? It had clear o-rings which I am pretty sure was on the original plugs, they then changed to black ones in the revised design. Hopefully I just avoided a destroyed TCU, unless whatever fluid is in the harness ends up still wicking into it. Maybe I will pull up the carpet and have a look at the TCU to be sure.

The transmission level afterwards was a bit high so sucked 400mL out. Probably need to add another 100mL now tomorrow and go for a proper drive for the higher temp reading.

MACEDON

Replace that socket/bushing then.

You''ll have to drain the fluid from the bottom, I think it's an 8mm you'll have to undo in the middle of the bushing, and then pull on it with your hand and it'll pop out

I doubt you'll have fluid wicked up to the TCU, clean your plug with electronic parts cleaner and you're good

Be careful when you install the new socket... oil the o-rings, push it nice and snug, and use the tiniest ratchet you can find to avoid overtightening it. You don't want to break the bushing on the conductor plate itself. If you have an OEM conductor plate they're pretty tough. I fudged it up on a super cheap $60 one from ebay, not once but twice.

Replace with OEM parts ONLY. Both the bushing and conductor plate if you ever have to do it.

And remember to check that cable from time to time for fluid, very easy to do with each oil change.

Lots of youtube videos out there on replacing that plug, i think the torque spec on the little 7 or 8mm screw is something to the tune of 2 N-m so be easy on it.


EDIT: OH wait I re read your post and you already changed it. Yeah the level can be tricky. Make sure your stick is to spec.

http://www.all-trans.by/assets/site/...es/722.6.1.pdf

This pdf will have info on the stick measurements. Drive the car for 20ish mins and it will definitely be at 80C since it's summer.

tw2

Yep I had purchased a new genuine one. The car has such low mileage that I was concerned it would be the original still in there. It was really easy to install, on the CLK55 I had to lever it in with a huge screw driver (yes pins and guides were perfectly aligned). This one on the E55 just pushed in with a bit of force from a finger and thumb.

It is 7mm socket and 2.5Nm but my smallest torque wrench only starts at 5Nm so I went with as tight as I could with my fingers and then a 90 degree turn with the wrench. Yep I have done the conductor plate on the CLK55 too, I bought "OEM" brand which according to pelicanparts was the OEM supplier to MB so same as the genuine item, I think it was $150-200 from memory.

Well on the dipstick today I got
- just under the top of the low temp range at 68 degrees F (20C).
- then 50mm fluid measurement from the end at 136 degrees F (58C) after a decent drive so it appears to be a little high (3mm) according to the chart bbirdwell was good enough to post. Do you guys think it is close enough to leave?

GM_Lover

You could try siphoning some out via the dipstick tube, but you might find like I did, that even 1/4 cup can mean the difference between a mm or two overfilled vs a mm or two underfilled. It was pretty frustrating, so I left it a mm or two overfilled when hot on my dipstick tool. I'm not worried such a small disparity.

On another note, I did the disconnect-line-and-drain method on my car. As far as I could tell, it'd never had the ATF changed in its 113K mile history (car had meticulous maintenance records and receipts and had zero mention of ATF change). Found an unsettling amount of metal flakes in the old ATF, so we'll see how long the trans holds up. It's a pretty common trans used across a bunch of cars across Mercedes and Chrysler/Jeep so not too worried about a rebuild or sourcing a replacement.

The trans runs great though for now (*knock on wood*). I don't know why anyone would only do a 40% (or whatever) change. I guess on a low mileage car like yours, it's fine, but there's almost no additional effort to pump out most of the rest.

tw2

Yes I found the same thing, add 400mL and I was still low. Add another 100mL and suddenly I am at the top of the range. I did a partial change because it is very easy. I don't have the adapters or experience to do the other method and the amount of ATF required would be about $400 here. I plan to do another partial change with my next engine oil change, just extract and refill, couldn't be easier.

tw2

Final update, a 20mL syringe fits perfectly onto my extractor pump tubing so I removed 60mL which took me from the high end of the 25degree range to the middle. Hot run, I cannot get over 59 degrees C ever, even with WOT on the open road. Anyway I got 47mm at 138 degrees F which is perfectly spot on for the graph.

I recommend taking out or adding only 50mL at a time if you are on the outer edge of the 25 degree range. Red lock clip installed.... until next time.