It's an aluminum heat-sink collar that wraps around the oil filter and supposedly lowers oil temperatures up to 12%. I was thinking about giving this a try since oil coolers are pretty pricy, require you to use 1.5 quarts more oil, and can break and cause more damage. They go for just under $20 though we all know it's about $4 of material...it took ingenuity to create this product though and we should support that; not make our own and mass-produce them.

Anyways, I was also thinking about adding a PC-CPU heatsink and fan to the filter while I'm at it. Kinda silly, but I have one lying around.

 

Why do you want to use an oil cooler? Do you autocross? Do you run boost?

Here is some interesting oil cooler info... if you lower the temp of the oil too much it can actually decrease the oil's effectiveness.

http://forums.maxima.org/showthread....ght=oil+cooler

 

Well, I always thought slightly cooler oil would be better...180-200 degrees sounds optimal. I don't drive the Maxima too hard, but I do take it to the track on occasion. I just thought an oil cooler would increase the longevity of the engine.

Also, I'm going to need an oil for my NA 89 Mazda 626. It runs really hot currently (steam rises from the oil filler after a normal drive). When I turbo swap that car, it comes with a stock oil cooler, but I know with a turbo...you're going to need more than that.