Last summer, my '91 740 leaked at the lower fitting of the hi-pressure hose. I cleaned it up and watched as the ATF squirted through a rust hole in the fitting.

I removed the hose, washed it clean with solvent, and ground through the pinhole with my Dremel -- and also another 6-10 rust spots that were pinholes waiting-to-happen.

And soldered 'em up using a propane torch and plumbing solder 'n flux (need clean steel for the solder to work).

$0.

So far, so good.

If you find the same problem and try the same approach, remember two things:

1) When removing and replacing the hose, pay attention to the copper washers used with the banjo bolt.

2) Do NOT use too much heat (or heat for too long). If you heat too much, you'll damage the seal between the hose and the metal fitting.

--
Don Foster (near Cape Cod, MA)