Ditto. I just changed my oil cooler gaskets in January after I developed a small oil leak. The oil cooler is located on the driver-side of the engine, maybe three inches away from the oil filter, it's a round looking thing with serrations in it. Replacment of the seals is a PITA, basically it requires draining the coolant (there's two coolnat lines which keep the oil cooler cool. Then remove the large (24 or 26mm I can't rember) bolt which holds the cooler on in the middle. One large gakset (probably the one that's leaking) will be located where the under-side of this cooler meets the block, the other one (small one) is located in the intereior of the cooler and requires removing a snap-ring to get to. Don't tell my truck but I only replaced the larger, outer seal and so far haven't had any problems with it leaking.

If it's any solace the parts guy at Toyota told me that these seals are one of the common failure points on the 3.0 V6, he couldn't belive I'd never replaced mine in the eight years I've owned my truck. Not sure if it makes any diffrece but up until last summer my truck was a daily driver and rarely sat for longer then four days at a time, now though it sits for a week or more at a time so I think that might have contribuited to the seal possibly drying-out, or not, it's hard to say.

HTH, sorry I don't have any pictures

--Kevin