C4 oil leak - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

ClevelandRocks · 10-12-2006, 18:13

Been trying to help my dad with a trans oil leak he has had all summer long. C4 in a 66 Mustang.

Tranny will drop a qt or so of oil but.... only after sitting more than 24 hrs on a level surface. It doesn't seem to blow or leak fluid while running and it sat 4 days on a slight uphill incline in my driveway without leaking a drop.

I have been unable to find the source of the leak. I replaced the tailshaft seal as I did see signs of oil at the snout but according to dad... it still leaks.

Pan gskt seems fine, no signs of fluid in modulator. I haven't seen the leak first hand so I don't even know the general area of where it is coming from.

Any ideas??

Dave

390wagon · 10-14-2006, 15:21

front seal probably, wont leak when sitting/not running but while running it will leak and come out the bellhousing.

GeDoubleYouSee · 11-16-2006, 16:26

Hello Clevelandrocks.
I have the same problem, if i take my pickup for a ride and park it for 2 or 4 hours there will not even be a drop under it. But when i park it in the garage over night, a shot glass will be under it "right below the filler tube". Just today i changed the filler tube o ring. Oh yea I know it is not the trans breather cause its on the other side and the tube is aimed where it would drop strait on the floor. I can do without leaks, but its un-ending drudgery keeping up with them. I will let you know how the o ring went. Oh yea, my filler tube was all cockeyed, yet another automotive Atrocitie that someone else eyeball engineered.

Hope all is well with you

GWC

ClevelandRocks · 11-16-2006, 17:07

Thanks GWC,

I appreciate the feedback. His car is in storage now and the leak has not yet been identified so I will be back at it in the spring. :-)

Looking forward to hearing from you after you've seen how the dipstick tube o-ring works out.

Dave

GeDoubleYouSee · 11-18-2006, 12:26

Dave,
Good news, The O-Ring solved the mystery. There was an alignment problem with the filler tube "who ever alignmented it was blind" So i bent up the bracket a half dozen time's to get the thing in the ball park and then mounted it and bent it the rest of the way. I was amazed how much oil that thing leaked, one time i put a tray down to catch the oil and it dripped over a quart in a month and only when it sat for a long time. While it runs the level never got near the O-Ring....but while sitting all the oil drained into the pan and rose above o-ring level. I know where most of the oil was coming from, My oil cooler i think, it is mounted way above the transmission. If you notice that a stock oil cooler on the radiator is lower than the pan "so most of the oil stays in the cooler" But when you put a larger trans oil cooler and mount it on the radiator higher than the lower tub on the radiator it all drains back into the transmission and that topped off with a bad alignment on filler tube with a bad o-ring. thats my theory anyway.

Gary