If you're currently in the market for a used semi-truck, then chances are you may have run across numerous trucks featuring engines that have undergone an overhaul at some point in their lives. Some truck dealers may even tout overhauled engines as an attractive selling point for buyers in search of long-lasting internals.

So is it a good or bad idea to buy a semi-truck with an overhauled engine? The following outlines the many advantages and disadvantages that come with making such a purchase. You'll also get a little advice about buying a used truck with a recently overhauled engine.

Benefits to Expect

Contrary to popular belief, engine overhauls aren't typically done due to the original engine being on its last legs. Instead, overhauls are usually performed as a preventative step towards getting the most out of a Class 8 diesel engine. The amount of overhaul work that's typically done to the engine depends on a variety of factors, including the number of hours on the engine and the level of overall wear and tear. A typical overhaul usually involves a near-complete teardown of the old engine and the replacement of certain wear items and other components with new counterparts. These include new cylinder heads, pistons, gaskets and main bearings, just to name a few.

Buying a used semi-truck with an overhauled engine has its benefits:

  • Buying a used truck with an overhauled engine can be like buying a brand-new truck, especially in terms of overall performance and fuel economy.
  • An overhauled engine can add years to a used truck's overall working life, making your used truck purchase a better long-term investment.
  • Buying a truck with an already-overhauled engine could also save you the hassle and expense of having your own engine overhaul done.
  • A used truck with an overhauled engine is also a bargain on the used truck market, especially when compared to newer trucks.

Drawbacks to Consider

In spite of the many advantages of buying a semi-truck with an overhauled engine, there are a few caveats to be aware of:

  • Without any documentation of the overhaul process, buying a truck with an overhauled engine can be a risky gamble. A lack of documentation should always raise a red flag during your search.
  • The quality of the work depends heavily on the shop tasked with the overhaul. Sloppy work performed by a shop with a less-than-stellar track record could easily result in eventual engine failure.
  • A used semi-truck may need additional maintenance and overhauling beyond the engine. For instance, a semi-truck may need a frame-up restoration due to severe chassis rust.

In some cases, you may be better off buying a used semi-truck and having your own overhaul done. Glider kits -- modern trucks that are largely rebuilt from the ground up using remanufactured engines and other components -- also offer another alternative to purchasing a brand-new truck.

Always Ask for Records

A complete set of service records can easily tell the tale about a semi-truck's previous life. This is especially true for trucks whose engines have undergone an overhaul at some point. Having these service records available can help you rest easier when it comes to your used purchase.

Whether you're buying from a used truck dealership or a private owner, you should always ask for a complete service history as well as all supplemental documents pertaining to the engine overhaul. If these records aren't available for some reason, then it's usually best to search elsewhere until you can find a similar truck with complete records.

In the end, it's up to you to decide whether you should purchase a semi-truck with an overhauled engine. The pros and cons listed above can help guide you towards the right choice for your trucking needs.