Oil drain bolt cross threaded help!

Hello, well the last time I got my oil changed I took my Trooper to a shop (of course the only time in years I’ve taken my vehicle to any shop). Now doing an oil change 3k later I see my drain bolt is cross threaded badly- I knew something was wrong when I just cracked the bolt loose and oil started leaking through the threads. A few questions-

My factory plug (2000 Isuzu Trooper 3.5L) is a m14x1.50, the threads don’t look terrible in the oil pan. Can I just take a m14 tap to clean the threads out and pop in a Fumoto drain valve? Or should I buy an oversize m15x1.50 tap/bolt?

The shop was a very highly rated one but in Colorado and I’m now living in Michigan so I can’t really have them help...



Expedition Leader
I'd have guessed the bolt steel would be harder than the pan, so my expectation would have been the pan to lose that fight. But if the threads look intact try a thread chaser and not a cutting tap to clean them. You don't want to remove any more metal than need and use a new bolt. I'd probably install it without any oil to make sure it's going to hold. If that doesn't work I'd use an insert, e.g. a Helicoil or Time-sert, to keep it a M14.
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