Hello everyone, since I’ve been putting lots of miles on the car I’ve just been going through the standard maintenance.

Last summer, I had some warranty work done for a leaking rear differential , where they replaced an axle seal, as well as a pinion seal. Since I was unsure of the causation, I asked them to change the breather in the diff as well. About two weeks ago while inspecting under the car, I noticed the rear diff was leaking again, so I checked the rear breather and saw it had not been replaced and was original to the car, covered in paint from the diff. for about nine dollars I bought what is called a diff breather, wiggle valve cap, I popped the old one out and popped the new one in and after about a week of driving, I haven’t noticed any new fluid. I did just top up the fluid today because it was a little bit low so I will monitor and report back if this fixed it. Stuck breathers can create issues on axles and diffs so make sure to check them.

I also did a transmission remove and replace of the fluid two times this weekend. It had been about five years and 20 to 25,000 miles since it had been done, last at the dealer. I’ve been having a little bit of hesitation at low speeds so figured it would be a good time to check up on the transmission. The hardest part of the whole process is getting the car level on jackstands and removing the under body panel. There’s plenty of videos out there on how to do this so I won’t go through that but here are some pics. I’ll report back after driving through the week, but the initial drive felt immediately smoother.

I did also change my transmission mount because I figured if it was bad I wanted to do it while I was under there. That was last changed in 2021 at the same time the transmission fluid was changed, but there was no cracking or any visual indication that the mount needed to be changed this time..


Overall the fluid was dirty but still had a blue hue


Not much debris on the pan, no sparkles

Magnet captured the fines. Very silt like and no size to any of the captured material.

 

Nicely done essential service!

I wonder how is this diff vent designed to fail reliably - It's one of those known items even Toyota features it...

The new tranny support is gonna help spare the prop shaft support bearing.

Would you mind sharing your favorite tranny video - I might tackle this service myself after I return home.

What blue ATF brand do you trust ?
What filter did you go with ?
What torque on new aluminum screws ?

Thank you.

 

Thanks Cali

I did go with the OEM AMG labeled part as well. The new mount definitely won’t hurt anything.

Differential and axle and transmission breathers are on every car that I know of. Because the fluid heats up the gases up top need to escape otherwise the fluid would come out of the weakest seal. They are a good thing. Many people hear about them in Toyota in the off-road community. My LX has breathers that are on tubes so you can ford deep water without having to worry about mucking up the breathers.

I’ll take a pic of my og valve with factory paint (
( in my opinion, the breather should’ve been installed after the diff was painted because that’s the guarantee to fail or cause axle issues) later today.

For this vehicle, the valve just pops off the barbed fitting.

rwd wagon location on passenger side top.

Stick something in here to make sure this barbed fitting is clean, especially if oil has been cooking in there. It means water has also likely gotten in. So change the fluid jig you’re unsure of quality.



I used an fcp kit to include pentosin, which is blue for the late trans. My 2013 has many of the features of the 2014 facelift in terms of everything but all wheel drive or body. I think because it’s a p30 car.

the kit had oem filter, unknown gasket I didn’t look for the label, pentosin, new bolts. You can get lm or Fuchs as well.

for torque I used 4nm, and then 180 degrees. New bolts are important here. Fortunately, I have torque wrenches for the lighter stuff because so many bolts are aluminum in the vehicles I’ve owned.

The exhaust bracket at the back of the pan did have to be removed in order to make access to those bolts and pan removal easier and clean

I used the FCP video which I can link later but I’ve got a roll to work now. I did the process twice at exactly 45°C. When changing the filter, I pumped in 5 L and then for the next replacement, I pumped in about two. I don’t know if there’s a drain plug on the wet clutch of this year model but I didn’t look. I’ll probably revisit this again shortly just to get some more fluid in there. I doubt when Mercedes did it that they drained all 12 or so quarts or liters.

So far so good and hopefully not famous last words