Depending on what time of year you shop, you can score some incredible discounts on a new pickup truck. It's not uncommon for Chevrolet to slap thousands of dollars in incentives on the hood of its Silverado model line, and this month, the stars have aligned to present just such an opportunity. September is an excellent month if you want to buy a 2020 Chevrolet Silverado 2500 HD, 3500 HD, or a previous-generation 2019 HD model, which is still in production.

The last-generation 2019 Silverado HD comes with the most aggressive offer, with $4,750 in customer cash. This deal is only valid on the four-door Crew Cab model, but buyers who opt for the LTZ or High Country trims with the 6.6-liter Duramax turbo-diesel V8 engine can qualify for an extra $750 rebate, bringing the total discount up to $5,500.

Chevrolet's 2020 Silverado HD discounts are just behind at $3,750 in customer cash. As with the 2019 model, the deal only applies to the Crew Cab body style, although you'll have to opt for the 6.6-liter diesel engine to score this incentive. Yet while the 2019 Silverado HD comes with a steeper discount for September, it actually carries a higher starting price than the 2020 model; unless your local dealer offers additional incentives on the 2019, we recommend opting for the newer truck.

As with all deals of this type, there are a few disclaimers to keep in mind. The deals are only good through September 30, 2020, so you'll need to take delivery before then to qualify. Chevy also notes that these incentives cannot be combined with any special finance or lease offers, nor certain other discounts, and not all customers will qualify for the customer cash. The promotion for the 2019 Silverado HD is not heavily advertised on Chevy's website, but you can see the deal on the pickup truck's online Build & Price tool.