Buying a used semi-truck isn’t like buying another used car, because you’re getting so much more than a vehicle. This purchase is an investment in your business. That is why it is even more important to take the time to carefully examine the semi you’re buying, and check various parts to ensure they’re in good condition. Knowing what parts to inspect is important to your success and having a vehicle that lasts long term.
Engine
The engine is the most important and expensive component of any semi, so it should be inspected carefully before you buy a used truck. Start by checking for visible oil leaks around the engine block, valve covers, and oil pan. Excessive oil buildup can indicate worn seals or gaskets that may need to be replaced very soon.
You should also listen to the engine while it’s running. Any unusual knocking or rattling sounds can be a sign of internal wear. Excessive exhaust smoke is another thing to watch out for. Blue smoke can indicate oil burning, while white smoke can point to coolant entering the combustion chamber.
Cooling System
The cooling system is as important as the engine in many ways. A failing cooling system will quickly damage your engine if left unchecked. So carefully inspect the radiator, water pump, coolant hoses, and clamps for corrosion or leaks. Overheating is extremely dangerous and can cause major engine damage. Worn cooling components are a common issue in older semis, so don’t skip this step.
Transmission and Clutch
The transmission on a semi-truck experiences a lot of stress, especially on rigs that have spent years hauling heavy loads already. Look over the system for fluid leaks around the transmission housing and examine the overall condition of the transmission fluid if you can. Burnt-smelling or dark transmission fluid indicates excessive wear.
You should also take the truck for a test drive and pay attention to how smoothly it shifts. Grinding sounds, burning smells, hesitation between gears, or slipping can be a sign of transmission problems that will likely be expensive to fix. For manual transmissions, carefully evaluate the clutch to make sure it doesn’t feel excessively loose. You also need to be on the lookout for a clutch that engages very high in the pedal travel, as this can indicate it’s nearing the end of its life.
Braking System
Because semi-trucks use air brakes, inspecting the brake components is necessary for safety. Examine the brake chambers and fittings for leaks or damage. Air leaks can compromise braking performance, which is a major safety concern. Check the condition of brake pads, rotors, and drums too. Excessive wear or scoring on them can be a sign that the braking system needs servicing, and possibly repairs.
If you are looking for used semi-trucks for sale in Dallas, always buy from a reputable dealer and take the time to inspect these components to ensure you’re getting a reliable rig.
