I assume you tried a friction oil filter, or end cap wrench first? If not and you haven't totally distorted the filter try one of those first. If that doesn't work, then try a large pair of channel locks and see if that works.

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2007 Tundra Limited Double Cab 4x4 Super White
Key FOB Tailgate Lock (courtesy of Toxarch)
OEM back-up camera w/flip down monitor
Sirius Satellite Radio
20" OEM alloy wheels
Line-X Bed liner
UWS Black Powdercoat Low Profile Toolbox
JC Whitney Black Nerf Bars
Lund Interceptor II Bug Shield
Tekonsha Voyager Brake Controller