The GMC CCKW

I'm looking for new oil filter lines. I took my 2 to a hose house and he wasn't familiar with the fittings. The nut rotates on the end like a brake line but is beveled and is the part that seals. These are 1/4" and cloth covered. Don't know the age but they are old. Any source for these. Also, one of the lines goes to the bolt that holds the fuel pump on. The bolt is hollow and the oil passes thru it. Are all 270 engines this way or is this unique to DUKW?

The trucks also had the oil return running through the fuel pump bolt, into the crankcase.
I understand the hose fittings to be special to GM.
The hoses can appear sound, then fail. I converted to NPT for practicality.

In the past I remember Joel Gopan had NOS hoses (or a source for them, at least).

I have been looking to replace the old, brittle rubber hoses that connect the oil filter to the engine. I would like to replace the "threaded sleeve nut" type fittings with something more conventional.

At first I was thinking about converting the existing lines and fittings to standard (-4) 37 deg AN type fittings. This would allow the use of any number of hose brands and types (Parker, Aeroquip, Earl's, etc. - either crimp-on or the reusable type).

However the more I looked at it, I don't see why the rubber lines could not be replaced with solid tubing. The oil filter is rigidly mounted, so its not like the lines need to provide for any degree of movement. If the elbow from the inlet was swapped out for a double flare elbow fitting, the line between the junction block and the filter could then be replaced with a single piece of steel tubing. Likewise for the return, although some work would need to be done in order to adapt the steel line to the hollow fuel pump bolt.

This would eliminate any future need to replace the rubber hoses - as they do have a finite life expectancy.

Any thoughts or comments on this would be greatly appreciated.

Best Regards...

I replaced mine with copper tubing; but I wound it into two coils about 2" diameter first, between the fittings, to help take up vibration & stress without cracking.