bass685

Been a lurker here for a long time and finally needed to make an account. I have a 2018 GMC Sierra All Terrain with the 5.3 / 8-speed, 22,000 miles, that was built in Mexico on 2/2018. Have noticed a coolant smell when walking around the truck for quite some time with a very slow level drop in the overflow tank. Did some searching on here and found the following two posts that seem to cover 2014 and 2015 truck with this problem. I do have one crack on the driver side aluminum which can be see in the photo attached. The smell is stronger when you get your nose near the area but I have not seen any visible staining or dripping yet. Wondering if anyone has had a truck outside of the TSB range with this problem and what you (and the dealer) did about it? Looking for any input before visiting the dealer. Thanks