What you need to know when buying a used commercial truck 

Whether venturing out as an owner operator for the first time, or re-entering the truck market after time in a fleet seat, there’s a lot to consider when making a used semi truck purchase. Class 8 commercial vehicles look like each other on the outside, but what matters most is what you can’t see from the side of the highway. So, with that in mind we’ve put together this used truck buyer’s guide. 

Know the latest rules and regulations 

First things first, know what’s legal. This goes to the state and federal level, but sometimes it can hit close to home with an ordinance restricting certain trucks and even the routes they’re allowed to take 

Start with a review of the truck’s specs. Chances are, if nothing has been seriously modified, you’ll be good. This is where buying from a reputable dealer can really save your bacon. For instance, all CSM dealerships will only sell used trucks that meet their local and federal statutes for big rigs.  

Don’t be afraid to reach out to your state DOT. There are numerous officers that will nail you when you stray from the law, but they’ll also help you answer important questions that might arise in the research phase of your purchase. With anything, results may vary.  

Used Commercial Truck Buyer’s Guide: Emissions  

Emissions standards are a category all their own. A lot of people are opting to buy older vehicles that are pre-emissions. That can be a serious gamble though. 

New Emissions Standards 

The government set ambitious goals to reach an overall reduction in oil consumption by 530 million barrels and greenhouse gas pollution by approximately 270 million metric tons. 

According to the EPA, when optimized to the new standards, a $50 billion savings can be realized for the sum of all vehicles built between 2014 and 2018. Of this figure, a class 8 truck might realize net fuel savings of $73,000 over ~ 435,000 miles traveled. The EPA says the investment in new tech is returned to the buyer within two years. 

Diesel Exhaust Fluid (DEF) is part of the equation for emissions. It’s a necessary evil to get the emissions where the government wants them. One OEM tried to build an engine that didn’t need DEF which led to disastrous results. The American Petroleum Institute (API) certifies proven DEF products.  

Some suggest making homemade DEF. This is a big-time no – don’t do it. Without the certification, the quality control, and the filtration manufacturers’ blessing, any resulting exhaust or engine failure is at the operator’s expense. The chances of the truck running right make the juice not worth the squeeze.  

Pre-Emission Trucks 

Any model year 2006 and older doesn’t need DEF and doesn’t have to comply to current EPA standards for emissions. A truck in this era might be ideal for small outfits, farmers, and short haulers. These trucks tend to have a lot of mileage and a lot of wear. 

Used Commercial Truck Buyer’s Guide: Mileage



Line Haul 

Line Haul miles are easy, but usually high in number. If there’s verifiable data to support the truck’s prior life in long distance transport. Line haul trucks tend to exceed a million miles before a complete overhaul. Results always vary.  

Regional Haul 

Regional haul is similar to line haul for a majority of the miles, however, there are typically more starts and stops. Those starts and stops tend to add up quickly, though. Decisions to buy a regional haul truck can work out well depending on the use the new owner has intended for the truck.  

Pick Up and Delivery Operations 

Common for day cabs, the pick-up and delivery truck operations have a lot of stop and go driving that isn’t always self-evident on the truck’s odometer. There’s a lot of engine time at delivery and pick up sites, as well as many stop lights.  

Vocational Operations 

Vocational trucks like dump trucks, wreckers, and cement mixers have a lot of engine hours and a lot of hard miles. The wear and tear is considerably higher than other trucking operations. Buyer beware when buying vocational equipment.  

Engine type and Horsepower


First, consider the intended use of the truck being purchased and the terrain where it will be driven. A line haul truck doesn’t always need 500 Horsepower, but if it’s hauling 78K pounds over the Rockies every other week, the loss in fuel economy might be worth the boost in power.   


Cab and Bunk 

Not needing a bunk can save a lot of up-front costs, but if you think you might need one, it’s highly recommended to have one. This is where smaller sleepers come in handy. Keep in mind the new ELD mandates and make the decision that suites your needs best.  


Consider these links or searching for links like them: 

The FED: 



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