[6d7gto]

What size grease fitting does the 1967 GTO 4 speed countershaft use? The hole is definitely 3/8" diameter but not sure which thread size to use. Is it tapered or straight? Any help is appreciated.

[lust4speed]

Talking about the Z-bar? I only have the one in my car and memory isn't good enough to remember when I welded up the original and made another to clear the Doug's header tube. If it looks like 3/8" diameter then it is a 1/8" NPT thread. If out of the car, a 1/8" pipe nipple should screw into the hole.

[6d7gto]

Originally Posted by lust4speed

Talking about the Z-bar? I only have the one in my car and memory isn't good enough to remember when I welded up the original and made another to clear the Doug's header tube. If it looks like 3/8" diameter then it is a 1/8" NPT thread. If out of the car, a 1/8" pipe nipple should screw into the hole.

Yes, Z bar...and it is out of the car. I believe you're right about it being pipe thread. A 3/8 x 24 screw fits but is sloppy. Thanks for your input. Bet you are correct in it being 1/8" pipe size which is tapered at 27 threads per inch.

Thanks again. Merry Christmas!

Robert

[6d7gto]

Got a 1/8"-27 NPT grease fitting today and it fits perfectly. Thanks Mick!

Robert