After changing the fluid in my late Porsche 915 box I noticed that I now have a significant leak coming from the region of one of the output flanges. My guess is this is a output flange seal. So while I am inthere I plan to change both sides.

I am looking for a descriptive "how to" for the procedure of changing these.

I am guessing that I will have to drain the box again (swepco is expensive)

Thanks

Did you overfill your trans?

If you are going to do it in place:

You may want to drain and catch some gear lube (if you want to reuse it). I would buy new. SWEPCO is still cheaper than rebuilding the trans. You shouldn't have to drain it all.

Remove axle shafts.
Remove output flanges.

Pull out old seal with suitable seal removal tool.
Drive in new seal (squarely). I stop when the seal is sitting flush with the housing at the seal itself.

Inspect the output flanges and if necessary, polish the area where the seal rubs.
Reinstall the output flanges.
Reinstall the axle shafts.

Refill the transmission with gear oil. (It's full when it starts draining out of the fill hole)

I usually replace them when the trans is apart, but I did a 901/914 box this way and it worked well.

Good luck to you.

Thank you!

No I don't think I overfilled it, I filled it till I could fill the fluid with my finger in the fill hole.

That is exactly what I was looking for.

It is always a good practice to lubricate seals on the sealing surface. Use the oil it will be sealing out. In this case transmission oil. If this step is omitted, the seal can wear the shaft causing a groove at the sealing area.