How To Turn Up A Paccar Engine – Expert Tips And Guide

You may be wondering about how to turn up a Paccar engine. 

Just like any responsible fleet owner or driver, you want to make sure that your engine is in good condition to keep it operating at its optimal condition. By keeping your vehicle tuned up as recommended by the manufacturer, this helps to prolong its lifespan, as well.

As a result, you can maximize the return on your investment. This also minimizes the need for serious repairs, which are more common with vehicles that are not well maintained.

With this in mind, you may want to consider learning more about the best ways to tune up your Paccar engine and ensure its performance, efficiency and overall condition. Find out just how you can do this by reading this post.

how to turn up a paccar engine

How To Turn Up A Paccar Engine

A Paccar engine has two important components – the DPF and EGR. These systems require proper maintenance as they are instrumental in the performance of your engine. The EGR reduces exhaust emissions of your diesel engine by simply diverting the exhaust gas inside through your EGR and mixed with an air intake.

Therefore, there is a constant reduction in the oxygen that gets into your engine. Thus, there is a lower combustion temperature. But the effect on your system is that there is carbon buildup that obstructs key components in your engine, thus minimizing efficiency.

As for the DPF, it prevents diesel particulates from being released into the air. The particulates remain in the DPF, and this reduces harmful exhaust that impacts the environment. Yet, the drawback is on the engine as it impacts not only its health but also its performance. 

Hence, these two systems require proper maintenance and servicing. This is particularly true with trucks that are usually in off-road situations.  To prevent the need for frequent, unnecessary and costly repairs that lead to longer downtimes, you need to keep these components in good condition through professional maintenance.

According to Paccar, there are a few other maintenance must-do’s to ensure the engine’s performance. 

For instance, a prolonged period of lower idle RPMs, as well as a high idle time, specifically at a low ambient temperature, combined with a low coolant temperature can lead to engine damage. This also impacts the aftertreatment system. This is why Paccar recommends maintaining the engine idle shutdown timer range to be at 25 degrees to 75 degrees Fahrenheit. With a longer idle between 25 and 35 degrees Fahrenheit, it is not possible to ensure a significant benefit to an operator.

Thus, if you keep your truck idle in a cool ambient temperature, you need to increase your engine speed to about 1,000 RPM. This helps to warm your cab up and achieve an optimal coolant temperature of around 150 degrees Fahrenheit. Once you have noticed that the temperature has warmed up, you can decrease your engine speed to 850 RPM. 

However, if you are idle for a longer period in a very cold ambient temperature, you will have to increase your engine speed of over 850 RPM. When you idle at a higher RPM, this produces more heat required to prevent soot buildup and clogging in your components.

When you have been idle for a longer time and this has triggered your DPF warning lamp to light up, you can do a stationary regen before driving your vehicle. 

If you experience premature cold-start cranking issues or failure, you can try turning your key to the on location, which lets the system complete all checks required before it starts the engine. 

Depending on what your truck application is, you may hear about four to six clicks, which is basically your ABS system performing a key-on check. You should know when the system completed the check once your release of the air compressor pressure release valve emits a burst of air. 

When it comes to filling your DEF tank, it is recommended to do this before the reservoir goes under 25 percent full. This same principle is applicable to your fuel system. You need to refill even before your fuel gauge is down to empty to prevent your system from running empty on fuel.

For the engine oil intervals, the recommended linehaul oil change interval is 40,000 miles when over 6 MPG. As for the vocational oil change, it is at 25,000 miles or about 800 hours, and this only applies once your fuel economy has gone down to under 6 MPG and over 80,000 GVW.

It is recommended that you replace both your frame mounted and engine mounted fuel filters as often as you replace your engine oil. 

As for your DEP filter, this needs to be replaced every 160,000 kms or 100,000 miles – or once a year. The initial style or white mesh should be replaced by a pleated type of paper filter.

For line haul, replace the filter every 200,000 miles and for vocational use, replace every 100,000 once a year with a pleated type of paper DEF filter.

Additional Points To Consider

Be sure to inspect your aftertreatment wiring and engine periodically and observe for signs of damage or wear. The valve adjustment must be completed at 40,000 miles or 1200 hours, then you need to do it once more at 160,000 miles or 4800 hours, then every 160,000 or 4800 hours throughout the lifespan of your vehicle.

Clean your DPF every 200,000 miles, and as for the EGR cooler, you need to clean this every 80,000 miles. 

Other components you should clean include the DEF doser nozzle, hydrocarbon doser, boost and the pressure sensor. Always make it a point to inspect these components for wear, damage or other issues that may be impacting their performance and condition. 

Read More: Paccar Px-7 Problems Not Many People May Know


These are just some of the basics to keep in mind when it comes to turning up your Paccar engine. We hope these tips have been helpful so you can ensure the optimal performance and lifespan of your precious investment.

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