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
