63 positraction fill plug

[Frank D.]

In replacing the missing "lube tag" on my differential fill plug I refer to the AIM and I see no other sealing part in the picture or description. I did also get the copper washer but is that used on the posi plug ? If so on which side of the "lube tag" does it go ?
Or does the "lube tag" serve the same purpose as the copper sealing washer all by itself ?

The plug currently has some fiber washer on it and no "lube tag"

[John F.]

Re: 63 positraction fill plug

Gasket is between the tag and the unit. Plug, posi tag, gasket! Gasket material is leather-like. Corvette Central #581074.

[Joe L.]

Re: 63 positraction fill plug

In replacing the missing "lube tag" on my differential fill plug I refer to the AIM and I see no other sealing part in the picture or description. I did also get the copper washer but is that used on the posi plug ? If so on which side of the "lube tag" does it go ?
Or does the "lube tag" serve the same purpose as the copper sealing washer all by itself ?

The plug currently has some fiber washer on it and no "lube tag"

Frank------


1963-64 differential uses straight thread for the filler plug and requires a gasket (originally leather). 1965-79 uses tapered thread and requires no gasket (but I advise using thread sealer).

[Frank D.]

Re: 63 positraction fill plug

Frank------


1963-64 differential uses straight thread for the filler plug and requires a gasket (originally leather). 1965-79 uses tapered thread and requires no gasket (but I advise using thread sealer).

Thanks fellas - that explains why my gasket is some fibrous material - it may be an original leather piece. So, I'm not sure whey vendors sell the copper version for 63/64. I'll fix it...

[Edward J.]

Re: 63 positraction fill plug

Thanks fellas - that explains why my gasket is some fibrous material - it may be an original leather piece. So, I'm not sure whey vendors sell the copper version for 63/64. I'll fix it...

Frank my 63 rear diff plug is a black fiber type material(as you say), I am not sure if its original but its a rather nice fit. i am sure just about anything will seal as long as if fit the plug nicely.

[Joe L.]

Re: 63 positraction fill plug

In replacing the missing "lube tag" on my differential fill plug I refer to the AIM and I see no other sealing part in the picture or description. I did also get the copper washer but is that used on the posi plug ? If so on which side of the "lube tag" does it go ?
Or does the "lube tag" serve the same purpose as the copper sealing washer all by itself ?

The plug currently has some fiber washer on it and no "lube tag"

Frank------


Here's an NOS GM #3714775, the original gasket:

[Frank D.]

Re: 63 positraction fill plug

Thanks Joe - I kept the one that came off the car and will get the grunge off it tomorrow and see if its leather or not and of the dimensions cited above. It wasn't causing a leak and not damaged so I'll clean it up and reinstall it if its original.