Just so you'll know, as I mentioned above, if we are talking about a GMC, a 250 series is a 1 ton, 280 series is a, 1 1/4 ton, a 300 series, is a 1 1/2 ton, a 350 series, is a 2 ton, a 400 series, is a 2 1/2 ton, a 450 series, is a 3 ton, & a 470 series, is a 3 1/2 ton. If this is a Chevy, a 3800 series is a 1 ton, a 4100, or 4400 series, is a 1 1/2 ton, & a 6100, 6400, & 6500 series are 2 tons.