solidhead

I replaced fluid on my 2011 sierra 1500 wt 2 wheel drive at 120k mi for the first time. I bought a new gasket and 3 bottles of AC-DELCO fluid from a dealership because I didn't know if after-market fluid works ok for my truck. old fluid was totally black and burnt. a shot glass full of metal powder was inside. Gear surfaces looked all in good condition. the truck has been a commuter vehicle with no towing or heavy load. After the fluid change, I did a 500 mi long trip in one day with no issue. I plan to do another fluid change at 180k mi or so.