I have been looking but cannot find the drain plug for the 9" ford diff I have been working on. Does anybody know the size so I can get a replacement. It is out of a 58 Ford Custom 300 4 Door. I hate when the gremlins take parts for a walk.
The carriers never had a drain plug, any drain was always on the housing. Ford installed drains in the '57, 58 and some '59 housings, after that they disappeared.
There are two types/sizes of plugs. The fill plugs are 1/2" NPT, drains are 3/8" NPT. If you're in a plumbing department, they'll have the standard pipe thread taper on the plug which isn't what you want. Most of these also have a square male head for tightening. Electrical/hydraulic plugs use the same thread minus the taper and will have a female socket for tightening; 3/8" for 1/2" and 5/16" for 3/8" in either square or hex (allen). The taper is in the female thread they go into.
Fill plug on the side of the pumpkin, Fill plug on the back of the case or no fill plug if you put the wrong combo together in the bought a third member and stuck it in my housing thing. I've got 4 nine inch housings, three F150 and one Galaxy and none have a drain plug and I don't ever think I saw a drain plug in one. Yuppers the photo is upside down so the rear is in the proper orientation.
Some of the factory plugs had a 5/16" square socket instead of a hex. Good thing I have lathe bits around. I replaced it with one that takes a hex key, from Ace Hardware.
When I take the pumpkin out of any Ford housing, I always add a welded on drain plug on the bottom of the housing. Makes it a lot less messy if you ever have to remove the pumpkin again.
If something in the road sticks up that high, I probably already have greater problems ahead of the rear end.This definitely isn't the lowest point on my car/truck.....so I'll risk it. The example below is not my car, but typical of the 32 I'm building.
Most floor jacks have a cupped shaped dish and I haven't had any problems when jacking cars up with this modification. Its actually pretty solid and works well for me. It helps that I picked up a couple of "drain plug" service boxes at an auction. Got lots of drain plugs for almost nothing.