Thanks for all of the advice.

Incidentally, I replaced both oil cooler hoses on another 300CD some years ago and used aftermarket hoses. I thus found out the hard way about the criticality of the ball at the end of each hose being smooth and having no burs. After installing a new hose on the connection to the bottom of the cooler, I had a leak. The solution was to use some emery cloth to remove a small bur (that I *eventually* noticed) on the ball to eliminate the leak by creating a perfect fit.

This time around, I desired to use oil cooler hose replacements sourced from M-B. It turns out that M-B no longer sells them for this vehicle.

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Question: Am I flirting with disaster by using, say, 10 seconds or so of MAPP gas on the *hose* (not cooler) nut fittings at the cooler to help loosen them?