Originally Posted by phunk

UPDATE: Pans are all going in the CNC again today for a quick change.

I am changing the oil drain plug threads from m12x1.25 to 9/16-18, which is also -6AN, which is of course a very popular thread.

Due to this change, I will be providing a new oil drain plug with all the pans.

Why did I make this change? The Nissan M12x1.25 did not pass my torque cycle testing. Its a very fine pitch thread for a M12, making it relatively weak. Having used aluminum pans with stock threads on the VQ before, I know how crappy the threads can get after a few oil changes. I originally thought that the higher quality billet aluminum would take this in stride, but I was wrong. Nissan intended this thread size for a steel pan, and thats just where it belongs.

Torque cycle testing was performed by soaking the threads and drain plug in oil, torquing, loosening, reapplying oil, repeat. Having oil on the washer surfaces and threads increases thread load tremendously.

Luckily, the washer pad on the oil pans was made just large enough diameter to accomodate -6 washers. So I am now running the pans through again and upgrading the threads for the drain plugs.

Moving forward, I am hoping to start cutting the oil pump pickup extensions tomorrow. I am also expecting the special cutter for the -10ORB ports to show up in the next day or two.