Relatively new to DIY auto repair and learning as I go. I've had my truck for about 4 years and am slowly going through everything. I am replacing the thermostat in the cooling system but am having an issue with leakage from the housing. I am using the upper and lower OEM gaskets that I bought from cool cruisers of Texas. Not sure what I am doing wrong. Happy to give more info if needed but looking for some guidance. Thanks