Oil Cooler Hose Sizing

[bobbiemartin]

I'm swapping a 97 506 block into a 1995 Suburban. The old engine had ½" oil cooler hoses that use 3/8" pipe fitting snap in adapters in the block. The new engine has oil squirters and 1/2" pipe fitting adapters but the actual hole for the oil cooler lines are the same as the 3/8 pipe adapters. Maybe I'm missing something, but shouldn't the 1/2" pipe adapters have a larger ID? Do the 5/8" oil hoses use the same size aluminum tubes? I see that the aftermarket oil cooler hoses only come in one size for all years, which I'm assuming is 1/2". Why did GM go with larger oil line adapters in the block only to keep the same size ID? I'm wondering if maybe this is a transitional block, perhaps GM was still using 1/2" oil lines and switched to 5/8" on later trucks? Is there any reason to use 5/8" oil hoses on oil squirter blocks? I will probably switch to aftermarket hose and want to get the correct size. Thanks for any help.

 

[bk95td]

Gm made the adapter fittings so the newer engines could be used in older trucks. My 97 has the #8[1/2] lines. I junked a 93 that had a 506 engine with the adapter fittings.
Pitstop usa sells the tru-cool oil cooler that fits the factory mounts[TRUM7B]$65. A hydraulics shop should be able to make hoses and have fittings.

 

[turbovanman]

Use 3/8 or 1/2 inch. I had 1/2 lines made up for my last job and they work great, figured they had the large fittings, might as well use them. :thumbsup: