I put one on a NV5600 last summer and a high mounted fill plug on my pto cover. I had to rebuild the trans. I only had one bearing go bad (it disintegrated) but until you catch the problem the metal filings are being tossed around screwing up the other parts. I bought the one from Quad 4x4 outfit it has two killer magnets with it, which I think are every bit as important as the filter. I haven't changed the oil yet, but I look at it like a bit of insurance. I didn't like doing that trans. I thought about one for the transfer case, it can't hurt. I had spent about a $500 on the trans parts plus a clutch, that hurt. I figured I would wait and see what the one looked like in the trans. On all of the transfer cases I have rebuilt I have never seen a oil related problem unless it was full of mud.
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93 250 2wd xc 354 auto 271k
04. 5 3500 4wd qc dully 373 6speed 94k