Do you know why it leaks? I chased a leak in 1 of my pickup’s tires; even a dip in the tub (what a mess!) didn’t turn it up. The llantero, who had a deeper tub, found it was the valve, which he fixed for $2.
If it’s a puncture, a puncture repair may work. If it’s a tiny leak, you can try sealant. Slime makes a version for utility vehicle tires, available at Walmart, etc.