Originally Posted by DODGE4x4
you tell a difference afterwards??
The first time, yes. The idle lowers, it runs smoother, and I get better gas mileage while it is in the tank. Now, I run it as maintenance. I would rather the engine stay clean, and have to run seafoam twice a year through the tank than wait until it gets really dirty.
So yes, I did feel a difference, but now I try to keep it clean enough so I don't have to notice a difference the next time I do it