'87 300TD transmission leak suggestions.
 

I have a leak somewhere on the drivers side of the transmission. I cleaned the whole side off so I would be able to get a better idea of where the leak was coming from. I tightened the the pan bolts a bit ( they weren't very tight). This seemed to help at first, but i don't think it actually did anything. The whole drivers side pan is wet and there is fluid dripping off of the speedo cable.

Can I assume that it is the electronic connector that is frequently talked about leaking? Are there any other likely suspects?

Also, it appears that the pan gasket has some silicone on it. It is sandwiched in, not applied to the outside. Is it worth cleaning or replacing the gasket? The fluid filter and gasket were replaced shortly before I got the car.

Best to find where the leak is before repairing it ;~)

The pan might have been bent from overtightening or other, and the silicone was an attempt to prevent a leak. It also could be installed without a gasket, just silicone. Or the pan might not be the source of the leak at all.

After several weeks it is still leaking. I think I finally identified it though. It looks like it is coming from the plug in the drivers side of the tranny with the 12mm allen key. I think it is the B1 piston.

Can this be solved by taking off the plug and replacing an O-ring? or does it involve removing the piston? How bad is this going to be?

if you have the old B2 Piston, might as well upgrade while your there

If I have to pull the tranny down, I will do whatever I can to extend the life of this transmission (290,000 miles and counting!). If I can stop this leak while it is in the car, then I will just do that for now. It performs beautifully when the fluid level is correct.

looking at the diagram, it looks like the plug comes out, the pressure body(?) comes out, and there are 2 o-rings on it. I just need someone with transmission experience to tell me that is no big deal to do.

I've never done it. I've read on it a little, I dont think you have to yank the trans out to do the B2. just need to move it over some

I believe that the B2 piston change is pre-'87, he probably has the later one.

SO the part in question appears to be the B1 pressure body, not the B1 Piston. I haven't the first clue about automatic transmissions. Can i pull this part out and replace the o-rings, or am I going to be dealing with annoying springs? putting a quart of $9 transmission fluid in every week and a half is getting annoying.