Oil Drain Plug Thread Size

caine0

Member
Jul 13, 2003
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I went down to Part Source and the guy told me he has two different sized drain plugs for my year mustang. What's the deal with this? I can't remember the two different sizes, but I have a 1990 LX 5.0. I need 2 new drain plugs cause mine are getting old.

What size do I need for both? He told me to take them out and bring him my drain plugs then we'll know, but I can't really take them out and drain my oil then take them to him, since I'll have no oil in my car. I don't really want to bum a ride from somebody just to do that. So hopefully he was just mistaken that there are the two different sizes

So can anyone tell me the proper size? Thanks. (I live in Canada too, but I think both systems are present on the packaging)
 
There are two sizes... On a 1990GT is 1/2-20 thread. It says so right on the head. The other size on some cars is 14mm. From what I know 1/2-20 is the most popular for 1990. I think 1/2-20 until Aug/1990 from what we looked up a week or so ago.