ATF leaking from line... WHAT PART IS IT? 300D
 

HI!
I patched it with JB Weld. :o But I'm pretty sure I ought to get a new one...
I'm driving a 1984 300D.

The tranny fluid line that is braced to the oil pan sprung a leak (dumped all over the Discount Tire parking lot!) What part is that? It is a metal line attached to the oil pan for support. The little bracket that holds it to the oil pan rubbed a hole in it and I thought my transmission had gone out! I don't even know how to find this part. OR any ideas for a sturdier cheap fix?

Also, did I overfill the ATF? UGH I never can tell. I added almost 6qts after as much as possible leaked out (couldn't get in gear at all, so I figured that was all of it).

This is my daily driver and I just need it to work like the beautiful beast that it is. (I'm a single mom of 4, and I'm in grad school.) I've been driving 300DT or 300TDTs since my first car 20 years ago --and consequently fixing them... yes I had a veggie machine back in my day.

Transmission fluid cooler line.

You could cut the line, flare the ends, then clamp a piece of transmission hose to join the two ends. Plenty of vehicles use that exact configuration between the hard lines and radiator.

It would also be worthwhile to check the other brackets that support the two cooler lines. Originally, they were "padded." The rubber or plastic pads disintegrate after a few decades, leaving the bare metal bracket to fret on the line. The pads can be replaced with some rubber or vinyl hose.

For a W123:
RH 123-270-40-96
LH 123-270-33-96

I got them for ~$50 each but that was a few years ago.

Happened to me a few years back. It was winter and snow on my driveway. I saw a trail of red drops in the snow and thought that a deer was injured and made it across my yard. Until I followed it to my garage and the only thing in my garage was my 300D. No deer. This is when I learned about the rubber liners on the transmission line supports. Mine were all hardened or missing. They can be replaced with an inexpensive rubber lined clamp that you will find in a good hardware store. As a temporary fix, I got a piece of fuel line at the auto parts store and used this as a sleeve, clamped it on with two hose clamps on each side, just to be safe. This held up fine until I got a replacement tranny line and installed it. I believe I got the tranny line here on the parts section. I just looked and do not see the tranny cooler line listed. My next step would be to call a Mercedes dealer to see if the part is still available. Take note of which line it is either left or right side. They are shaped differently. If it is not available, then a mechanic or tranny shop can bend a new line for you.

I will add that to install the sleeve, I needed to cut the existing line through to be able to insert it. I measured the outside diameter of the tranny cooler line and matched it up with the inside diameter of the fuel line. There is not much pressure in that line so the hose clamps will hold just fine.

Thank you so much, ya'all!

Not feeling like cutting the line right now since I just poured $25 of fluid in, so I just wrapped a split open heater hose around my JB weld and clamped that on there for support.

It seems to be leaking all over the place from above, which I guess means that I did overfill it.

I'm going to look for those remaining support brackets!
The name of the game is "Replace the Rubber & Plastic Bits!"

A good post w/ photos ~10 yrs ago with same problem of "clamp wore thru tranny cooler tube". After reading that, I added isolators to all my clamps w/ missing factory plastic ones. I slit polybutylene tube and slid over the metal tube. Except 1 clamp on my 1985 I just couldn't loosen since right above the K-frame where hard to get to. I spent >30 min w/ various wrenches before I gave up.

As long as you don't cut (or disconnect) a cooling line with the transmission operating (ie: engine running), you won't loose more than a token amount of transmission fluid.

The grommets are 1129970281

:hanged2:

I didn't change the line fast enough. I figured a leak was okay as long as I kept adding fluid. I bought everything I needed and was going to change it today, but had to drive yesterday to get my kids. IT WAS A VERY BAD MOVE.

Now my transmission is DEAD.

Okay, I dropped the pan and it was full of bright, clean fluid. No particles, no sludge. It smelled kinda like sulfur.

Do I now suspect the torque converter?

It depends on the description of dead.

It may be a B2 piston problem. Are you getting any movement, forward or reverse?

Picking kids up from school I was going forward at highway speeds after some hesitation in lower gears.

On the way back I wasn't going very well at all and then couldn't even feel the car shift into reverse or into drive. Finally it shifted into reverse and at VERY HIGH RPMs barely backed out of the spot it was in.

(Unfortunately) my ex kindly had it towed to his house (40 miles away), where the donor vehicle is. I am waiting for the opportunity to change the line and fill the ATF back up and see what happens after it gets warm. If I'm lucky he will do it for me and let me know how it goes.

It failed to go into reverse or forward. Finally shifted into reverse and was barely able to back out into the spot behind it.
From my understanding a B2 failure wouldn't have trouble going into reverse?

You may be fortunate. Mine broke at the transmission. Thankfully, once I got the new line installed and filled the fluid, it came to life again. It took some cycling through the gears to get it to behave.