Big-block Oil Coolers Can Get in Your Way, but There’s a Solution

Gen V and VI Chevy big blocks make motor swaps hard with their standard cooling solutions. Thankfully, Hot Rod has a quick fix.

If you have ever considered swapping in a big block Chevy engine from 1991 to 2001 into a different platform, you have likely encountered the oil cooler issue. Say you find yourself with a cheap Suburban K2500 with the Vortec 7400. You’ve got 454 cubic-inches of raw Chevy metal ready for you to pluck, but as you pull it out, though, you notice an issue: There’s an oil cooler, and the lines for it run straight into the block beside the oil filter. Where are you going to put an oil cooler on your prized project car? Is there a way to delete it?

If by chance, this happens to be your situation, we’ve got great news for you. The fine folks over at Hot Rod have put together a helpful little diagram and instruction set. While it may be tempting to throw a couple of bolts in there, you might run into some leaking issues. Worse yet, you may make it a little challenging to fit your oil pan. So, short of just retrofitting the oil cooler somewhere in the car you’re swapping it into, what do you do?

Luckily, it’s a relatively simple solution. Firstly, remove the oil pan fittings from positions A and B in the diagram, and replace them with standard pipe plugs. This is important as if you use standard bolts, you’ll run into oil pan fitment issues, as previously discussed.  In position C on the diagram sits a pressure relief valve, that you’ll want to retain.

However, there is a higher flow version available (GM PN 25013759). There is another relief valve in position D that sits in the opening for the oil filter; you’ll want to remove that one. Finally, all you need to do is install a standard Chevy V8 Oil Filter. The one pictured is AC Delco’s PF454.

There you have it! Let your swap opportunities open entirely. Though the LS-based small block is well-proven for making power, sometimes you just need a big-block. Grab yourself a big block and plop it in something cool, because now you know how to get around those oil cooler lines!

Photos: Hot Rod

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Braden Carlson

Braden Carlson is an automotive enthusiast from Boise, Idaho. At 19 he quit his day job to pursue a career in automotive journalism, launching his Youtube channel in his own name. Today you can still find him producing DIY video content, reviews and writing for an amassment of automotive websites. His work is most frequently found on Rennlist, The Mustang Source and Corvette Forum. When not writing or driving, he's likely to be found covered in grease and oil undoubtedly from one of his gratuitous collection of questionable project cars.