Hello all. I had a heck of a time finding the proper filter kit and fluid for my wife's '13 Cadillac SRX AWD rear axle clutch. It's a Haldex unit, and GM acts like these are non-serviceable. It's an easy job once you're under the car. I had a little issue of one of the bolts recessed in the middle of the filter cover being so rusted that the 4mm hex couldn't bite well enough to loosen it. An easy-out worked in this case (they aren't very tight from the factory.) Remove 10 4mm hex bolts, remove the cover. Here's the inside of the cover: There was also a fair amount of sludge inside the unit as well. I cleaned it out carefully with brake cleaner. This is the filter/gasket kit from GM, made in Germany: (found for around $30 on eBay) New filter and gasket in place: Replace the filter cover and snug up the bolts. The filter cover has a fill plug on the side of it. Fill it until it's full. Drive the car for 5 minutes, then top off. (I didn't top off initially, and the car threw a "Service rear axle" code.) Here's the fluid from GM, made in Sweden and about $60 a quart if you shop around. (I got mine off eBay.) My '14 Regal has the same setup, but the unit is buried in a contour of the underbody of the car, with the exhaust covering it for good measure. I'm going to break down and have a shop do that one, as it will require dropping the exhaust and rear differential to access it. Hope this helps someone out!