:welcome:, What year Enclave do you have? Does the car move or sway when the tank sloshes? I noticed mine will slosh when it is full to about 5/8 tank, but does'nt move or anything it just make a sound. p.s. fill in your vehicle signature with all the stuff your Enclave has, this helps us down the road :thumb:. I see you posted on the Enclave forum as well, they will help you with more vehicle specifics.