Hey guys, I just did a fluid and filter change on my 300TD's automatic transmission. I drained both the pan and torque converter. I did not drain the trans cooler.

I buttoned her up and checked for leaks while she was running and found none. I backed her out of my stall at work, left her running, cleaned up, checked for leaks again, then drove home.

When I came out to my car there was a very small bit of ATF under her. Because it was coming from the torque converter area, I was worried I hadn't tightened its drain plug correctly, so I put her on jack stands and turned the motor over by hand until I could see the drain plug and it was dry. In fact the entire TC looked dry on inspection. I wiped off the bell housing grate under the TC and wiped up the puddle and let her run for ten or so minutes in my driveway, still at 80 degrees celsius.

There were no visible leaks.

Prior to the service the trans pan had a moderate leak at the gasket, but not at the TC. The pan gasket is no longer leaking.

Is there any way to explain ATF leaking from the near the TC while driving but not while in park? I think I may have just done a poor job cleaning up after draining the TC, but I've not driven it since parking it earlier this afternoon.

An interesting dilemma I've ran into is an oil funnel that doesnt fit tight into the dipstick tube. Upon refill, some of the fluid will seep out of the tube, and down the transmission. Maybe check the top of the bell housing, or along the dipstick tube for atf.

Did you check the level after driving, and before shutting off? My only guess is that it is possibly overfilled, foaming and coming out the vent? If not, IDK.

__________________

Gone to the dark side

- Jeff

It's not overfilled, I don't think. Level is right on the money idling in park at 80 degrees celsius.

I'm thinking it is the front pump seal. I must not have noticed the leak before because the leak at the pan was so bad.

It's not bad enough for me to really worry about it. I will just have to live with it for now, monitor the fluid level and eventually get a junkyard trans to rebuild/reseal.

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1984 300TD - der Landstreicher

If it is the front pump seal, you can change it without removing the front pump, but you do need the trans out and TC removed.

__________________

Gone to the dark side

- Jeff