How much does a bus engine cost?

In today’s blog post, we will answer the following question: How much does a bus engine cost? We will discuss what type of engines buses have and whether it is best to repair or replace them all together when converting a Skoolie

How much does a bus engine cost?

The cost for replacing a bus engine will vary greatly depending on the type of engine you need, the manufacturer, horsepower, torque and year of manufacture. The price range for a new bus engine is between $3,500 to $14,500, highly influenced by the market you decide to buy. 

Engine typeManufacturerHorsepowerTorquePrice range
DT 466International Navistar300 hp @ 2,200 rpm860 lb-ft @ 1,300 rpm$4,500 – $9,500
T444eInternational Navistar275 hp525 lb-ft$3,500 – $11,500
5.9LCummins325 hp610 lb-ft$4,600 – $10,000
8.3LCummins400 hp1075 lb-ft$3,500 – $11,500
CAT 3126Caterpillar330 hp860 lb-ft$7,500 – $14,500
CAT 3116Caterpillar350 hp735 lb-ft$6,500 – $13,500

How long does a bus engine last and when do I have to replace it?

Most Skoolies have diesel engines that last 15 to 20 years or 250,000 miles if properly maintained and treated with care. 

In rare cases, the Skoolie engines will not even get to seven years, as the causes of wear and breakdowns are plenty. As the diesel engines were equipped with new components over the years, new failures related to these parts appeared. In rare cases, motorists have even witnessed the breakage of these parts. 

Frequent breakdowns in diesel school bus engines today include:

  • The injection pump,
  • The injectors,
  • The EGR valve,
  • The particulate filter, however essential to reduce the number of fine particles emitted in the exhaust.
  • The turbo, which tends to clog and is one of the common causes of engine failure.
  • The dual-mass flywheel, a transmission part commonly found on diesel models and known to break more often than rigid flywheels.

However, it must be admitted that manufacturers now master the design of these parts. While faults can still be observed on certain ranges, the fouling and breakage of engine parts are on the whole less numerous.

Is it best to replace or repair a bus engine?

Many drivers consider buying a new bus engine in the event of a broken one or in the process of converting a Skoolie. It starts from the concept that the engine is considered the heart of the vehicle. If this organ is broken down, the vehicle is no longer really of much use.

A bus engine is expensive. The first thing to do is determine if you really need a new engine. Before deciding, you should check with a reliable technician whether the damage is repairable. If replacement turns out to be a must, then again, it makes more sense to compare.

Buying used bus engines is much more affordable. On sites such as Autoline, you will find a large selection of used parts for different manufacturers, in addition to the engine. The used engines have been reconditioned to manufacturer standards by qualified technicians. They are therefore reliable products. Driving with a used engine pays off in the long run. The latter has the advantage of outlasting the original engine.

Replacing the engine is often essential when the mechanics of the vehicle are affected and the repairs are substantial. Change is particularly necessary when key parts that are difficult and expensive to repair are concerned. This is the case, for example, with a broken timing belt on a diesel engine. The valves are deformed. The camshaft is broken into several pieces. It is also impossible to save the breech. A hole in the crankcase, an engine running out of steam are other reasons for buying a new engine.

To avoid any worries in the future, it is recommended that you have your engine replaced by a professional.

Is a diesel or gasoline engine better for a Skoolie?

Historically, diesel engines have long been considered more enduring than their gasoline counterparts. One of the reasons for this is that a diesel engine runs slower than a gasoline vehicle. In addition, until the 1980s, diesel vehicles benefited from a simpler design, which promoted high reliability.

Later, however, these engines were made more complex. They are now equipped with turbo and high-pressure injectors. These additions have improved the performance of each car, but also undermined their reliability: these parts are now responsible for many breakdowns.

Today’s diesel vehicles no longer correspond to the opinion still anchored in many minds, who consider that this type of fuel is synonymous with an indestructible engine.

But if the diesel models have seen their robustness decline in recent decades, they remain on average more enduring than the petrol versions. If thermal engines (diesel as gasoline) would have a similar lifespan, a diesel model would travel on average 16,000 miles per year, compared to 9,300 annually for gasoline. 

In terms of mileage, the average lifespan of diesel would therefore be 155,000 miles, compared to 60,000 miles less for gasoline.

How to prevent damage to a bus engine?

Most problems related to the turbocharger can be avoided with regular maintenance of your car. To prevent turbo failures, be sure to regularly change the engine to replace the oil and filter. 

Also, be sure to check the engine oil level and clean the air filter. By doing this, you are ensuring that your turbocharger stays in good condition for as long as possible and you avoid early repairs or replacement.

One of the most common problems is turbocharger fouling from debris or dirt in the oil.

A lack of oil in the engine can damage the turbine engine irreversibly and lead to an expensive replacement. Conversely, too much engine oil can raise the temperature and damage the turbine engine. Most problems with excessively high temperatures are triggered by faults in the ignition or fuel injection system.

The maintenance of the fuel system and school bus engine is quite simple. The main point is to keep the diesel in your Skoolie clean and fresh. Pollution and debris are the number one cause of failure in this system.

It is recommended to replace your Skoolie’s fuel filter annually or every 15,000 miles. approximately. Additionally, the entire system should be cleaned through a professional decarbonization service to minimize the build-up of fuel by-products.

The bottom line

Bus engines are always more sophisticated, so it is more difficult for them to be damaged, even if it is more expensive to repair them. These days, saving on repair and maintenance of the bus and extending its lifespan is essential. 

If you do decide to replace your bus engine, we recommend you let a professional guide or do all the work. Proper installation is vital.

Please feel free to get in contact should you have any comments on the content. 

FAQ on How much does a bus engine cost?

Do school buses get good gas mileage?

Yes, school buses get good gas mileage. A Skollie can get an average of 10 miles per gallon, which is pretty good for a bus. 

What is the best diesel engine for an RV?

If your budget allows it, the best diesel engine for a motorhome is an engine greater than 100 hp. You will have more comfort with a more powerful and more torquey engine, especially if you are travelling with a large payload. 

How to make the best of your diesel engine?

The following tips should help you reduce your fuel consumption and take the best from your diesel engine. A motorhome consumes between 12 and 30 litres per 100 kilometres depending on the engine and the size, we assume that if you take the road in a motorhome, it is certain that you are going on vacation or for the weekend.

What engines do school buses have?

Most American school buses have a diesel engine. Currently, Skoolies and Skoolies mostly use diesel as fuel, although there are quite a few initiatives to switch to Gas, less to electricity and occasionally to hydrogen. 

How does a school bus engine work?

A school bus diesel engine works by igniting (igniting) the fuel by being injected with a high-pressure spray into a combustion chamber (or pre-chamber, in the case of indirect injection) containing air at a temperature higher than the self-combustion temperature, with no need for a spark. 


Was this helpful?

Thanks for your feedback!